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    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_BD366B734B7A8C88C0E9FC6CC13A24F9_terseLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearTwo_BD366B734B7A8C88C0E9FC6CC13A24F9" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">2016</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour" xlink:label="loc_us-gaap_FiniteLivedIntangibleAssetsAmortizationExpenseYearFour_13C084F22317F4FD02AFFC6CC13B0B17" xlink:type="locator" />
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    <link:label id="lab_us-gaap_FiniteLivedIntangibleAssetsNet_044D2C85F0728A75B82AFC6CC13BDD0B_totalLabel_en-US" xlink:label="lab_us-gaap_FiniteLivedIntangibleAssetsNet_044D2C85F0728A75B82AFC6CC13BDD0B" xlink:role="http://www.xbrl.org/2003/role/totalLabel" xlink:type="resource" xml:lang="en-US">Total</link:label>
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    <link:label id="lab_nx_SellEURMember_9B2924FEDBF0C7F1E776FCBF9C251733_documentation_en-US" xlink:label="lab_nx_SellEURMember_9B2924FEDBF0C7F1E776FCBF9C251733" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sell EUR [Member]</link:label>
    <link:loc xlink:href="nx-20190731.xsd#nx_SellEURMember" xlink:label="loc_nx_SellEURMember_9B2924FEDBF0C7F1E776FCBF9C251733" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_nx_SellEURMember_9B2924FEDBF0C7F1E776FCBF9C251733" xlink:to="lab_nx_SellEURMember_9B2924FEDBF0C7F1E776FCBF9C251733" xlink:type="arc" />
    <link:label id="lab_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47_terseLabel_en-US" xlink:label="lab_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sell CAD, buy USD</link:label>
    <link:label id="lab_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47_label_en-US" xlink:label="lab_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sell CAD [Member]</link:label>
    <link:label id="lab_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47_documentation_en-US" xlink:label="lab_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sell CAD [Member]</link:label>
    <link:loc xlink:href="nx-20190731.xsd#nx_SellCADMember" xlink:label="loc_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47" xlink:to="lab_nx_SellCADMember_09EDBD778A1CBE8B5EC5FCBF9C254D47" xlink:type="arc" />
    <link:label id="lab_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7_terseLabel_en-US" xlink:label="lab_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Sell GBP, buy USD</link:label>
    <link:label id="lab_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7_label_en-US" xlink:label="lab_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Sell GBP [Member]</link:label>
    <link:label id="lab_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7_documentation_en-US" xlink:label="lab_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Sell GBP [Member]</link:label>
    <link:loc xlink:href="nx-20190731.xsd#nx_SellGBPMember" xlink:label="loc_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7" xlink:to="lab_nx_SellGBPMember_B13218BB087E7CD4FA8CFCBF9C25A1A7" xlink:type="arc" />
    <link:label id="lab_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76_terseLabel_en-US" xlink:label="lab_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Buy EUR, sell GBP</link:label>
    <link:label id="lab_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76_label_en-US" xlink:label="lab_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Buy EUR, sell GBP [Member]</link:label>
    <link:label id="lab_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76_documentation_en-US" xlink:label="lab_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Buy EUR, sell GBP [Member]</link:label>
    <link:loc xlink:href="nx-20190731.xsd#nx_BuyEurSellGbpMember" xlink:label="loc_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76" xlink:to="lab_nx_BuyEurSellGbpMember_17353904E0B0C236AF80FCBF9C25CE76" xlink:type="arc" />
    <link:label id="lab_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F_terseLabel_en-US" xlink:label="lab_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Buy GBP, Sell EUR [Member]</link:label>
    <link:label id="lab_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F_label_en-US" xlink:label="lab_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Buy GBP, Sell EUR [Member]</link:label>
    <link:label id="lab_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F_documentation_en-US" xlink:label="lab_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Buy GBP, Sell EUR [Member]</link:label>
    <link:loc xlink:href="nx-20190731.xsd#nx_BuyGBPSellEURMember" xlink:label="loc_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F" xlink:to="lab_nx_BuyGBPSellEURMember_F351A08E0861157DDA3DFCBF9C26A54F" xlink:type="arc" />
    <link:label id="lab_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E_terseLabel_en-US" xlink:label="lab_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Buy USD, Sell EUR</link:label>
    <link:label id="lab_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E_label_en-US" xlink:label="lab_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Buy USD, Sell EUR [Member]</link:label>
    <link:label id="lab_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E_documentation_en-US" xlink:label="lab_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E" xlink:role="http://www.xbrl.org/2003/role/documentation" xlink:type="resource" xml:lang="en-US">Buy USD, Sell EUR</link:label>
    <link:loc xlink:href="nx-20190731.xsd#nx_BuyUSDSellEURMember" xlink:label="loc_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E" xlink:to="lab_nx_BuyUSDSellEURMember_33C042495A96A51F9092FCBF9C26A00E" xlink:type="arc" />
    <link:label id="lab_us-gaap_DerivativesFairValueLineItems_1D727747476DFFB4BA58FCBF9C261676_terseLabel_en-US" xlink:label="lab_us-gaap_DerivativesFairValueLineItems_1D727747476DFFB4BA58FCBF9C261676" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivatives, Fair Value [Line Items]</link:label>
    <link:label id="lab_us-gaap_DerivativesFairValueLineItems_1D727747476DFFB4BA58FCBF9C261676_label_en-US" xlink:label="lab_us-gaap_DerivativesFairValueLineItems_1D727747476DFFB4BA58FCBF9C261676" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivatives, Fair Value [Line Items]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DerivativesFairValueLineItems" xlink:label="loc_us-gaap_DerivativesFairValueLineItems_1D727747476DFFB4BA58FCBF9C261676" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DerivativesFairValueLineItems_1D727747476DFFB4BA58FCBF9C261676" xlink:to="lab_us-gaap_DerivativesFairValueLineItems_1D727747476DFFB4BA58FCBF9C261676" xlink:type="arc" />
    <link:label id="lab_invest_DerivativeNotionalAmount_4102C26C4B9E373DBDDAFCBF9C269D7F_terseLabel_en-US" xlink:label="lab_invest_DerivativeNotionalAmount_4102C26C4B9E373DBDDAFCBF9C269D7F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Derivatives, notional amount</link:label>
    <link:label id="lab_invest_DerivativeNotionalAmount_4102C26C4B9E373DBDDAFCBF9C269D7F_label_en-US" xlink:label="lab_invest_DerivativeNotionalAmount_4102C26C4B9E373DBDDAFCBF9C269D7F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Derivative, Notional Amount</link:label>
    <link:loc xlink:href="http://xbrl.sec.gov/invest/2013/invest-2013-01-31.xsd#invest_DerivativeNotionalAmount" xlink:label="loc_invest_DerivativeNotionalAmount_4102C26C4B9E373DBDDAFCBF9C269D7F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_invest_DerivativeNotionalAmount_4102C26C4B9E373DBDDAFCBF9C269D7F" xlink:to="lab_invest_DerivativeNotionalAmount_4102C26C4B9E373DBDDAFCBF9C269D7F" xlink:type="arc" />
    <link:label id="lab_us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet_7AD42B94DDCFAAB013EBFCBF9C273D1F_terseLabel_en-US" xlink:label="lab_us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet_7AD42B94DDCFAAB013EBFCBF9C273D1F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Foreign currency derivatives, fair value</link:label>
    <link:label id="lab_us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet_7AD42B94DDCFAAB013EBFCBF9C273D1F_label_en-US" xlink:label="lab_us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet_7AD42B94DDCFAAB013EBFCBF9C273D1F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Foreign Currency Derivative Instruments Not Designated as Hedging Instruments at Fair Value, Net</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet" xlink:label="loc_us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet_7AD42B94DDCFAAB013EBFCBF9C273D1F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet_7AD42B94DDCFAAB013EBFCBF9C273D1F" xlink:to="lab_us-gaap_ForeignCurrencyDerivativeInstrumentsNotDesignatedAsHedgingInstrumentsAtFairValueNet_7AD42B94DDCFAAB013EBFCBF9C273D1F" xlink:type="arc" />
    <link:label id="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_A26D468CBF9E2AE921E7FC69E7B13318_terseLabel_en-US" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_A26D468CBF9E2AE921E7FC69E7B13318" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]</link:label>
    <link:label id="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_A26D468CBF9E2AE921E7FC69E7B13318_label_en-US" xlink:label="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_A26D468CBF9E2AE921E7FC69E7B13318" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Schedule of Effective Income Tax Rate Reconciliation [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock" xlink:label="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_A26D468CBF9E2AE921E7FC69E7B13318" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_A26D468CBF9E2AE921E7FC69E7B13318" xlink:to="lab_us-gaap_ScheduleOfEffectiveIncomeTaxRateReconciliationTableTextBlock_A26D468CBF9E2AE921E7FC69E7B13318" xlink:type="arc" />
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_64B56853CBFF7C0AFB31FC69E79E741F_terseLabel_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_64B56853CBFF7C0AFB31FC69E79E741F" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Table Text Block]</link:label>
    <link:label id="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_64B56853CBFF7C0AFB31FC69E79E741F_label_en-US" xlink:label="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_64B56853CBFF7C0AFB31FC69E79E741F" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Disaggregation of Revenue [Table Text Block]</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_DisaggregationOfRevenueTableTextBlock" xlink:label="loc_us-gaap_DisaggregationOfRevenueTableTextBlock_64B56853CBFF7C0AFB31FC69E79E741F" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_DisaggregationOfRevenueTableTextBlock_64B56853CBFF7C0AFB31FC69E79E741F" xlink:to="lab_us-gaap_DisaggregationOfRevenueTableTextBlock_64B56853CBFF7C0AFB31FC69E79E741F" xlink:type="arc" />
    <link:label id="lab_us-gaap_OperatingIncomeLoss_C4E6738F2B94BE1698CCFC69E74F5044_verboseLabel_en-US" xlink:label="lab_us-gaap_OperatingIncomeLoss_C4E6738F2B94BE1698CCFC69E74F5044" xlink:role="http://www.xbrl.org/2003/role/verboseLabel" xlink:type="resource" xml:lang="en-US">Operating loss</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_OperatingIncomeLoss" xlink:label="loc_us-gaap_OperatingIncomeLoss_C4E6738F2B94BE1698CCFC69E74F5044" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_OperatingIncomeLoss_C4E6738F2B94BE1698CCFC69E74F5044" xlink:to="lab_us-gaap_OperatingIncomeLoss_C4E6738F2B94BE1698CCFC69E74F5044" xlink:type="arc" />
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_A5977ABEE44DED60FD0CFC69E568281C_terseLabel_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_A5977ABEE44DED60FD0CFC69E568281C" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Number of shares authorized, originally</link:label>
    <link:label id="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_A5977ABEE44DED60FD0CFC69E568281C_label_en-US" xlink:label="lab_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_A5977ABEE44DED60FD0CFC69E568281C" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Share-based Compensation Arrangement by Share-based Payment Award, Number of Shares Authorized</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized" xlink:label="loc_us-gaap_ShareBasedCompensationArrangementByShareBasedPaymentAwardNumberOfSharesAuthorized_A5977ABEE44DED60FD0CFC69E568281C" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_CommitmentsAndContingenciesDisclosureTextBlock" xlink:label="loc_us-gaap_CommitmentsAndContingenciesDisclosureTextBlock_8487BBC25922C8B7EDFDFC69E6F10CD2" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOperatingCapitalAbstract" xlink:label="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_0D268F34471232556BB3E3C5C4931198" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_0D268F34471232556BB3E3C5C4931198" xlink:to="lab_us-gaap_IncreaseDecreaseInOperatingCapitalAbstract_0D268F34471232556BB3E3C5C4931198" xlink:type="arc" />
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    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccountsAndNotesReceivable_3BE3E2B4875101441494E3C5C493E491" xlink:to="lab_us-gaap_IncreaseDecreaseInAccountsAndNotesReceivable_3BE3E2B4875101441494E3C5C493E491" xlink:type="arc" />
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    <link:label id="lab_us-gaap_IncreaseDecreaseInInventories_8EE1BC88413E7C807458E3C5C4939DEE_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInInventories_8EE1BC88413E7C807458E3C5C4939DEE" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Inventories</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOtherOperatingAssets" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingAssets_C69B6EA898C10350B3DEE3C5C494E445" xlink:type="locator" />
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    <link:label id="lab_us-gaap_IncreaseDecreaseInAccountsPayable_B5DC78BF4DC73990AAB8E3C5C494501E_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccountsPayable_B5DC78BF4DC73990AAB8E3C5C494501E" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase in accounts payable</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccountsPayable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccountsPayable_B5DC78BF4DC73990AAB8E3C5C494501E" xlink:type="locator" />
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedLiabilities" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_B2CAD21F786C7FB29ECBE3C5C4940689" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccruedLiabilities_B2CAD21F786C7FB29ECBE3C5C4940689" xlink:to="lab_us-gaap_IncreaseDecreaseInAccruedLiabilities_B2CAD21F786C7FB29ECBE3C5C4940689" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_AE2955BDEED87A787DA1E3C5C4949270_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_AE2955BDEED87A787DA1E3C5C4949270" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase in income taxes payable</link:label>
    <link:label id="lab_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_AE2955BDEED87A787DA1E3C5C4949270_label_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_AE2955BDEED87A787DA1E3C5C4949270" xlink:role="http://www.xbrl.org/2003/role/label" xlink:type="resource" xml:lang="en-US">Increase (Decrease) in Income Taxes Payable</link:label>
    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable" xlink:label="loc_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_AE2955BDEED87A787DA1E3C5C4949270" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_AE2955BDEED87A787DA1E3C5C4949270" xlink:to="lab_us-gaap_IncreaseDecreaseInAccruedIncomeTaxesPayable_AE2955BDEED87A787DA1E3C5C4949270" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations_338BD7025EEC615C3148E3C5C494DA80_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations_338BD7025EEC615C3148E3C5C494DA80" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">Increase in deferred pension and postretirement benefits</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations" xlink:label="loc_us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations_338BD7025EEC615C3148E3C5C494DA80" xlink:type="locator" />
    <link:labelArc order="1" xlink:arcrole="http://www.xbrl.org/2003/arcrole/concept-label" xlink:from="loc_us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations_338BD7025EEC615C3148E3C5C494DA80" xlink:to="lab_us-gaap_IncreaseDecreaseInPensionAndPostretirementObligations_338BD7025EEC615C3148E3C5C494DA80" xlink:type="arc" />
    <link:label id="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_D6F62ECBAD1539F4236EE3C5C494E9E1_terseLabel_en-US" xlink:label="lab_us-gaap_IncreaseDecreaseInOtherNoncurrentLiabilities_D6F62ECBAD1539F4236EE3C5C494E9E1" xlink:role="http://www.xbrl.org/2003/role/terseLabel" xlink:type="resource" xml:lang="en-US">(Decrease) increase in other long-term liabilities</link:label>
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    <link:loc xlink:href="http://xbrl.fasb.org/us-gaap/2018/elts/us-gaap-2018-01-31.xsd#us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet" xlink:label="loc_us-gaap_IncreaseDecreaseInOtherOperatingCapitalNet_45D646DF97CA685F321DE3C5C49503D7" xlink:type="locator" />
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