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<!-- Generated by DFIN XBRL Schema Document - http://www.dfinsolutions.com/ - on 15-05-2026 02:08:15 PM -->
<!-- Copyright(c) 2026 Donnelley Financial Solutions, Inc. All Rights Reserved. -->
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					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain" xlink:to="C000173507Member" order="51.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000173506Member" xlink:label="C000173506Member"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain" xlink:to="C000173506Member" order="52.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000227966Member" xlink:label="C000227966Member"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain" xlink:to="C000227966Member" order="53.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000227965Member" xlink:label="C000227965Member"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain" xlink:to="C000227965Member" order="54.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000227967Member" xlink:label="C000227967Member"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="ShareClassDomain" xlink:to="C000227967Member" order="55.0"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/Other1CategoryOnly">               
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_OtherCategory1Domain" xlink:label="OtherCategory1Domain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/Other2CategoryOnly">               
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_OtherCategory2Domain" xlink:label="OtherCategory2Domain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/LargestHoldingOnly">               
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_LargestHoldingsDomain" xlink:label="LargestHoldingsDomain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/SalesLoadOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_WithSalesLoadMember" xlink:label="WithSalesLoadMember"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://fasb.org/us-gaap/role/eedm/ExtensibleEnumerationLists">               
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentTypeCategorizationMember" xlink:label="InvestmentTypeCategorizationMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USGovernmentDebtSecuritiesMember" xlink:label="USGovernmentDebtSecuritiesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="USGovernmentDebtSecuritiesMember" order="1.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ExchangeTradedFundsMember" xlink:label="ExchangeTradedFundsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="ExchangeTradedFundsMember" order="2.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ServiceMember" xlink:label="ServiceMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="ServiceMember" order="3.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HealthCareMember" xlink:label="HealthCareMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="HealthCareMember" order="4.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MunicipalBondsMember" xlink:label="MunicipalBondsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="MunicipalBondsMember" order="5.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_ForeignGovernmentSecuritiesMember" xlink:label="ForeignGovernmentSecuritiesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="ForeignGovernmentSecuritiesMember" order="6.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_LeveragedLoansMember" xlink:label="LeveragedLoansMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="LeveragedLoansMember" order="7.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_AllOtherCorporateBondsAndNotesMember" xlink:label="AllOtherCorporateBondsAndNotesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="AllOtherCorporateBondsAndNotesMember" order="8.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_IndustrialsMember" xlink:label="IndustrialsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="IndustrialsMember" order="9.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_EnergyMember" xlink:label="EnergyMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="EnergyMember" order="10.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_FinancialsMember" xlink:label="FinancialsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="FinancialsMember" order="11.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_CorporateBondsAndNotesMember" xlink:label="CorporateBondsAndNotesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="CorporateBondsAndNotesMember" order="12.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherInvestmentsMember" xlink:label="OtherInvestmentsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="OtherInvestmentsMember" order="13.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MortgageBackedSecuritiesMember" xlink:label="MortgageBackedSecuritiesMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="MortgageBackedSecuritiesMember" order="14.0"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermInvestmentsMember" xlink:label="ShortTermInvestmentsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="ShortTermInvestmentsMember" order="15.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_AffiliatedExchangeTradedFundMember" xlink:label="AffiliatedExchangeTradedFundMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="AffiliatedExchangeTradedFundMember" order="16.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_OtherIncludesShortTermInvestmentMember" xlink:label="OtherIncludesShortTermInvestmentMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="OtherIncludesShortTermInvestmentMember" order="17.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember" xlink:label="OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember" order="18.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_AffiliatedMutualFundsMember" xlink:label="AffiliatedMutualFundsMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="AffiliatedMutualFundsMember" order="19.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_InformationTechnologyMember" xlink:label="InformationTechnologyMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="InformationTechnologyMember" order="20.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_GamingLeisureMember" xlink:label="GamingLeisureMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="GamingLeisureMember" order="21.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_ManufacturingMember" xlink:label="ManufacturingMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="ManufacturingMember" order="22.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_FoodTobaccoMember" xlink:label="FoodTobaccoMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="FoodTobaccoMember" order="23.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_AllOtherLeveragedLoansMember" xlink:label="AllOtherLeveragedLoansMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="AllOtherLeveragedLoansMember" order="24.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_OtherIncludesSecuritiesLendingCollateralMember" xlink:label="OtherIncludesSecuritiesLendingCollateralMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="InvestmentTypeCategorizationMember" xlink:to="OtherIncludesSecuritiesLendingCollateralMember" order="25.0"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/BroadBasedIndexOnly">               
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_BroadBasedIndexDomain" xlink:label="BroadBasedIndexDomain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/AdditionalIndexOnly">              
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_AdditionalIndexDomain" xlink:label="AdditionalIndexDomain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/MaturityOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_MaturityDomain" xlink:label="MaturityDomain"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/IndustrySectorOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_IndustrySectorDomain" xlink:label="IndustrySectorDomain"/>
					<link:loc xlink:type="locator" xlink:href="#vot_HealthCareREITSMember" xlink:label="HealthCareREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="HealthCareREITSMember" order="1.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_IndustrialOfficeREITSMember" xlink:label="IndustrialOfficeREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="IndustrialOfficeREITSMember" order="2.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_RetailREITSMember" xlink:label="RetailREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="RetailREITSMember" order="3.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_DataCentersREITSMember" xlink:label="DataCentersREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="DataCentersREITSMember" order="4.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_ResidentialREITSMember" xlink:label="ResidentialREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="ResidentialREITSMember" order="5.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_SelfStorageREITSMember" xlink:label="SelfStorageREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="SelfStorageREITSMember" order="6.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_SpecialtyREITSMember" xlink:label="SpecialtyREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="SpecialtyREITSMember" order="7.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_OtherREITSMember" xlink:label="OtherREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="OtherREITSMember" order="8.0"/>
					<link:loc xlink:type="locator" xlink:href="#vot_RealEstateManagementAndDevelopmentREITSMember" xlink:label="RealEstateManagementAndDevelopmentREITSMember"/>
					<link:definitionArc xlink:type="arc" xlink:arcrole="http://xbrl.org/int/dim/arcrole/domain-member" xlink:from="IndustrySectorDomain" xlink:to="RealEstateManagementAndDevelopmentREITSMember" order="9.0"/>
				</link:definitionLink>
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/CreditQualityOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_CreditQualityDomain" xlink:label="CreditQualityDomain"/>
				</link:definitionLink>
				<!--GeographicRegionOnly use only for STPR-->
				<link:definitionLink xlink:type="extended" xlink:role="http://xbrl.sec.gov/oef/role/GeographicRegionOnly">
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/oef/2025/oef-2025.xsd#oef_GeographicRegionDomain" xlink:label="GeographicRegionDomain"/>
				</link:definitionLink>
				<link:labelLink xlink:type="extended" xlink:role="http://www.xbrl.org/2003/role/link">               
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_USGovernmentDebtSecuritiesMember" xlink:label="USGovernmentDebtSecuritiesMember"/>
					<link:label xlink:type="resource" xlink:label="label_USGovernmentDebtSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">US Government Debt Securities [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="USGovernmentDebtSecuritiesMember" xlink:to="label_USGovernmentDebtSecuritiesMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ExchangeTradedFundsMember" xlink:label="ExchangeTradedFundsMember"/>
					<link:label xlink:type="resource" xlink:label="label_ExchangeTradedFundsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Exchange Traded Funds [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="ExchangeTradedFundsMember" xlink:to="label_ExchangeTradedFundsMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ServiceMember" xlink:label="ServiceMember"/>
					<link:label xlink:type="resource" xlink:label="label_ServiceMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Service [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="ServiceMember" xlink:to="label_ServiceMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_HealthCareMember" xlink:label="HealthCareMember"/>
					<link:label xlink:type="resource" xlink:label="label_HealthCareMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Health Care [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="HealthCareMember" xlink:to="label_HealthCareMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MunicipalBondsMember" xlink:label="MunicipalBondsMember"/>
					<link:label xlink:type="resource" xlink:label="label_MunicipalBondsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Municipal Bonds [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="MunicipalBondsMember" xlink:to="label_MunicipalBondsMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_ForeignGovernmentSecuritiesMember" xlink:label="ForeignGovernmentSecuritiesMember"/>
					<link:label xlink:type="resource" xlink:label="label_ForeignGovernmentSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Foreign Government Securities [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="ForeignGovernmentSecuritiesMember" xlink:to="label_ForeignGovernmentSecuritiesMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_LeveragedLoansMember" xlink:label="LeveragedLoansMember"/>
					<link:label xlink:type="resource" xlink:label="label_LeveragedLoansMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Leveraged Loans [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="LeveragedLoansMember" xlink:to="label_LeveragedLoansMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_AllOtherCorporateBondsAndNotesMember" xlink:label="AllOtherCorporateBondsAndNotesMember"/>
					<link:label xlink:type="resource" xlink:label="label_AllOtherCorporateBondsAndNotesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">All other Corporate Bonds and Notes [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AllOtherCorporateBondsAndNotesMember" xlink:to="label_AllOtherCorporateBondsAndNotesMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_IndustrialsMember" xlink:label="IndustrialsMember"/>
					<link:label xlink:type="resource" xlink:label="label_IndustrialsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Industrials [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="IndustrialsMember" xlink:to="label_IndustrialsMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_EnergyMember" xlink:label="EnergyMember"/>
					<link:label xlink:type="resource" xlink:label="label_EnergyMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Energy [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="EnergyMember" xlink:to="label_EnergyMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_FinancialsMember" xlink:label="FinancialsMember"/>
					<link:label xlink:type="resource" xlink:label="label_FinancialsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Financials [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="FinancialsMember" xlink:to="label_FinancialsMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_CorporateBondsAndNotesMember" xlink:label="CorporateBondsAndNotesMember"/>
					<link:label xlink:type="resource" xlink:label="label_CorporateBondsAndNotesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Corporate Bonds and Notes [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="CorporateBondsAndNotesMember" xlink:to="label_CorporateBondsAndNotesMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000176707Member" xlink:label="C000176707Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000176707Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000176707 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000176707Member" xlink:to="label_C000176707Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000176707Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class R6</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000176707Member" xlink:to="label_C000176707Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000003575Member" xlink:label="C000003575Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000003575Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000003575 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000003575Member" xlink:to="label_C000003575Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000003575Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class I</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000003575Member" xlink:to="label_C000003575Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000003574Member" xlink:label="C000003574Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000003574Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000003574 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000003574Member" xlink:to="label_C000003574Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000003574Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class C</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000003574Member" xlink:to="label_C000003574Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000003572Member" xlink:label="C000003572Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000003572Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000003572 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000003572Member" xlink:to="label_C000003572Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000003572Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class A</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000003572Member" xlink:to="label_C000003572Member_2"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_OtherInvestmentsMember" xlink:label="OtherInvestmentsMember"/>
					<link:label xlink:type="resource" xlink:label="label_OtherInvestmentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Other Investments [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="OtherInvestmentsMember" xlink:to="label_OtherInvestmentsMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_MortgageBackedSecuritiesMember" xlink:label="MortgageBackedSecuritiesMember"/>
					<link:label xlink:type="resource" xlink:label="label_MortgageBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Collateralized Mortgage-Backed Securities [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="MortgageBackedSecuritiesMember" xlink:to="label_MortgageBackedSecuritiesMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetBackedSecuritiesMember" xlink:label="AssetBackedSecuritiesMember"/>
					<link:label xlink:type="resource" xlink:label="label_AssetBackedSecuritiesMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Asset-Backed Securities [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AssetBackedSecuritiesMember" xlink:to="label_AssetBackedSecuritiesMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_ShortTermInvestmentsMember" xlink:label="ShortTermInvestmentsMember"/>
					<link:label xlink:type="resource" xlink:label="label_ShortTermInvestmentsMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Short-Term Investments [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="ShortTermInvestmentsMember" xlink:to="label_ShortTermInvestmentsMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049901Member" xlink:label="C000049901Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049901Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049901 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049901Member" xlink:to="label_C000049901Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049903Member" xlink:label="C000049903Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049903Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049903 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049903Member" xlink:to="label_C000049903Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049904Member" xlink:label="C000049904Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049904Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049904 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049904Member" xlink:to="label_C000049904Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000148854Member" xlink:label="C000148854Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000148854Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000148854 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000148854Member" xlink:to="label_C000148854Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_HealthCareREITSMember" xlink:label="HealthCareREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_HealthCareREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Health Care REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="HealthCareREITSMember" xlink:to="label_HealthCareREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_IndustrialOfficeREITSMember" xlink:label="IndustrialOfficeREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_IndustrialOfficeREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Industrial Office REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="IndustrialOfficeREITSMember" xlink:to="label_IndustrialOfficeREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_RetailREITSMember" xlink:label="RetailREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_RetailREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Retail REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="RetailREITSMember" xlink:to="label_RetailREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_DataCentersREITSMember" xlink:label="DataCentersREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_DataCentersREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Data Centers REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="DataCentersREITSMember" xlink:to="label_DataCentersREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_ResidentialREITSMember" xlink:label="ResidentialREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_ResidentialREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Residential REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="ResidentialREITSMember" xlink:to="label_ResidentialREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_SelfStorageREITSMember" xlink:label="SelfStorageREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_SelfStorageREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Self Storage REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="SelfStorageREITSMember" xlink:to="label_SelfStorageREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_SpecialtyREITSMember" xlink:label="SpecialtyREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_SpecialtyREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Specialty REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="SpecialtyREITSMember" xlink:to="label_SpecialtyREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_OtherREITSMember" xlink:label="OtherREITSMember"/>
					<link:label xlink:type="resource" xlink:label="label_OtherREITSMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Other REITS [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="OtherREITSMember" xlink:to="label_OtherREITSMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000176708Member" xlink:label="C000176708Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000176708Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000176708 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000176708Member" xlink:to="label_C000176708Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000119169Member" xlink:label="C000119169Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000119169Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000119169 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000119169Member" xlink:to="label_C000119169Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049913Member" xlink:label="C000049913Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049913Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049913 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049913Member" xlink:to="label_C000049913Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049915Member" xlink:label="C000049915Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049915Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049915 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049915Member" xlink:to="label_C000049915Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049917Member" xlink:label="C000049917Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049917Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049917 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049917Member" xlink:to="label_C000049917Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000081781Member" xlink:label="C000081781Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000081781Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000081781 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000081781Member" xlink:to="label_C000081781Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000148855Member" xlink:label="C000148855Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000148855Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000148855 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000148855Member" xlink:to="label_C000148855Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_AffiliatedExchangeTradedFundMember" xlink:label="AffiliatedExchangeTradedFundMember"/>
					<link:label xlink:type="resource" xlink:label="label_AffiliatedExchangeTradedFundMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Affiliated Exchange Traded Fund [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AffiliatedExchangeTradedFundMember" xlink:to="label_AffiliatedExchangeTradedFundMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_OtherIncludesShortTermInvestmentMember" xlink:label="OtherIncludesShortTermInvestmentMember"/>
					<link:label xlink:type="resource" xlink:label="label_OtherIncludesShortTermInvestmentMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Other includes short term investment [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="OtherIncludesShortTermInvestmentMember" xlink:to="label_OtherIncludesShortTermInvestmentMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember" xlink:label="OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember"/>
					<link:label xlink:type="resource" xlink:label="label_OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Other includes short term investment and securities lending collateral [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember" xlink:to="label_OtherIncludesShortTermInvestmentAndSecuritiesLendingCollateralMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000176709Member" xlink:label="C000176709Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000176709Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000176709 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000176709Member" xlink:to="label_C000176709Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000066828Member" xlink:label="C000066828Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000066828Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000066828 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000066828Member" xlink:to="label_C000066828Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049921Member" xlink:label="C000049921Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049921Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049921 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049921Member" xlink:to="label_C000049921Member"/>
										<link:label xlink:type="resource" xlink:label="label_C000049921Member_2" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xml:lang="en-US">Class C1</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049921Member" xlink:to="label_C000049921Member_2"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049920Member" xlink:label="C000049920Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049920Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049920 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049920Member" xlink:to="label_C000049920Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049918Member" xlink:label="C000049918Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049918Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049918 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049918Member" xlink:to="label_C000049918Member"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_EnergySectorMember" xlink:label="EnergySectorMember"/>
					<link:label xlink:type="resource" xlink:label="label_EnergySectorMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Energy Sector [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="EnergySectorMember" xlink:to="label_EnergySectorMember"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_RealEstateSectorMember" xlink:label="RealEstateSectorMember"/>
					<link:label xlink:type="resource" xlink:label="label_RealEstateSectorMember" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Real Estate Sector [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="RealEstateSectorMember" xlink:to="label_RealEstateSectorMember"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000049922Member" xlink:label="C000049922Member"/>
					<link:label xlink:type="resource" xlink:label="label_C000049922Member" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">C000049922 [Member]</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="C000049922Member" xlink:to="label_C000049922Member"/>
					<link:loc xlink:type="locator" xlink:href="#vot_C000066829Member" xlink:label="C000066829Member"/>
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					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_AssetsNet" xlink:label="AssetsNet"/>
					<link:label xlink:type="resource" xlink:label="label_AssetsNet" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Net Assets</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="AssetsNet" xlink:to="label_AssetsNet" priority="1"/>
					<link:loc xlink:type="locator" xlink:href="https://xbrl.fasb.org/us-gaap/2025/elts/us-gaap-2025.xsd#us-gaap_InvestmentCompanyPortfolioTurnover" xlink:label="InvestmentCompanyPortfolioTurnover"/>
					<link:label xlink:type="resource" xlink:label="label_InvestmentCompanyPortfolioTurnover" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">Investment Company Portfolio Turnover</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="InvestmentCompanyPortfolioTurnover" xlink:to="label_InvestmentCompanyPortfolioTurnover" priority="1"/>                
					<link:loc xlink:type="locator" xlink:href="https://xbrl.sec.gov/dei/2025/dei-2025.xsd#dei_NoTradingSymbolFlag" xlink:label="dei_NoTradingSymbolFlag"/>
					<link:label xlink:type="resource" xlink:label="label_NoTradingSymbolFlag" xlink:role="http://www.xbrl.org/2003/role/label" xml:lang="en-US">No Trading Symbol Flag</link:label>
					<link:labelArc xlink:type="arc" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="dei_NoTradingSymbolFlag" xlink:to="label_NoTradingSymbolFlag" priority="1"/>		
				</link:labelLink>
			</link:linkbase>
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	</annotation>   
	<element name="ForeignGovernmentSecuritiesMember" id="vot_ForeignGovernmentSecuritiesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="LeveragedLoansMember" id="vot_LeveragedLoansMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
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	<element name="IndustrialsMember" id="vot_IndustrialsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="EnergyMember" id="vot_EnergyMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="FinancialsMember" id="vot_FinancialsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
	<element name="CorporateBondsAndNotesMember" id="vot_CorporateBondsAndNotesMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
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	<element name="IndustrialOfficeREITSMember" id="vot_IndustrialOfficeREITSMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
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	<element name="AffiliatedMutualFundsMember" id="vot_AffiliatedMutualFundsMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
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	<element name="RealEstateManagementAndDevelopmentREITSMember" id="vot_RealEstateManagementAndDevelopmentREITSMember" type="dtr-types:domainItemType" substitutionGroup="xbrli:item" abstract="true" nillable="true" xbrli:periodType="duration"/>
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</schema>
