Gupta, P. (2005). six sigma performance handbook: A statistical guide to optimizing results. McGraw-Hill.
Čikaški stil citiranjaGupta, Praveen. Six Sigma Performance Handbook: A Statistical Guide to Optimizing Results. USA: McGraw-Hill, 2005.
MLA način citiranjaGupta, Praveen. Six Sigma Performance Handbook: A Statistical Guide to Optimizing Results. McGraw-Hill, 2005.
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