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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherLongtermProvisions" xlink:label="ifrs-full_OtherLongtermProvisions" xlink:type="locator"/>
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxLiabilities" xlink:label="ifrs-full_DeferredTaxLiabilities" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_DeferredTaxLiabilities"
                            order="30.0"
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentFinancialLiabilitiesAtAmortisedCost" xlink:label="ifrs-full_NoncurrentFinancialLiabilitiesAtAmortisedCost" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_NoncurrentFinancialLiabilitiesAtAmortisedCost"
                            weight="1.0"
                            order="31.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentLeaseLiabilities" xlink:label="ifrs-full_NoncurrentLeaseLiabilities" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_NoncurrentLeaseLiabilities"
                            weight="1.0"
                            order="32.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentDerivativeFinancialLiabilities" xlink:label="ifrs-full_NoncurrentDerivativeFinancialLiabilities" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentLiabilities"
                          xlink:to="ifrs-full_NoncurrentDerivativeFinancialLiabilities"
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   <link:calculationLink xlink:role="https://www.gvs.com/xbrl/role/all/ias_1_role-210000" xlink:type="extended">
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentAssets" xlink:label="ifrs-full_NoncurrentAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_Assets"
                          xlink:to="ifrs-full_NoncurrentAssets"
                            order="10.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentAssets" xlink:label="ifrs-full_CurrentAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_Assets"
                          xlink:to="ifrs-full_CurrentAssets"
                            order="20.0"
                            weight="1.0"
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   <link:calculationLink xlink:role="https://www.gvs.com/xbrl/role/all/ias_1_role-210000" xlink:type="extended">
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentAssets" xlink:label="ifrs-full_NoncurrentAssets" xlink:type="locator"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_PropertyPlantAndEquipment" xlink:label="ifrs-full_PropertyPlantAndEquipment" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_PropertyPlantAndEquipment"
                            order="10.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_DeferredTaxAssets" xlink:label="ifrs-full_DeferredTaxAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_DeferredTaxAssets"
                            order="100.0"
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                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_OtherNoncurrentFinancialAssets" xlink:label="ifrs-full_OtherNoncurrentFinancialAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_OtherNoncurrentFinancialAssets"
                            order="120.0"
                            weight="1.0"
                          xlink:type="arc"/>
      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_RightofuseAssets" xlink:label="ifrs-full_RightofuseAssets" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_RightofuseAssets"
                            weight="1.0"
                            order="121.0"
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_NoncurrentDerivativeFinancialAssets" xlink:label="ifrs-full_NoncurrentDerivativeFinancialAssets" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_NoncurrentDerivativeFinancialAssets"
                            weight="1.0"
                            order="122.0"
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_IntangibleAssetsAndGoodwill" xlink:label="ifrs-full_IntangibleAssetsAndGoodwill" xlink:type="locator"/>
      <link:calculationArc
                          xlink:arcrole="http://www.xbrl.org/2003/arcrole/summation-item"
                          xlink:from="ifrs-full_NoncurrentAssets"
                          xlink:to="ifrs-full_IntangibleAssetsAndGoodwill"
                            weight="1.0"
                            order="123.0"
                          xlink:type="arc"/>
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   <link:calculationLink xlink:role="https://www.gvs.com/xbrl/role/all/ias_1_role-210000" xlink:type="extended">
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_Inventories" xlink:label="ifrs-full_Inventories" xlink:type="locator"/>
      <link:calculationArc
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                          xlink:from="ifrs-full_CurrentAssets"
                          xlink:to="ifrs-full_Inventories"
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                            order="1"
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      <link:loc xlink:href="http://xbrl.ifrs.org/taxonomy/2020-03-16/full_ifrs/full_ifrs-cor_2020-03-16.xsd#ifrs-full_CurrentTaxAssetsCurrent" xlink:label="ifrs-full_CurrentTaxAssetsCurrent" xlink:type="locator"/>
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                          xlink:from="ifrs-full_CurrentAssets"
                          xlink:to="ifrs-full_CurrentTaxAssetsCurrent"
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                          xlink:from="ifrs-full_CurrentAssets"
                          xlink:to="ifrs-full_OtherCurrentFinancialAssets"
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                          xlink:to="ifrs-full_OtherCurrentNonfinancialAssets"
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                          xlink:to="ifrs-full_Equity"
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