Eckes George. (2005). Six sigma execution: How to World's greatest companies live and breathe six sigma (sách photo) (In lần thứ 1.). American: McGraw-Hill.
Παραπομπή Chicago StyleEckes George. Six Sigma Execution: How to World's Greatest Companies Live and Breathe Six Sigma (sách Photo). In lần thứ 1. American: McGraw-Hill, 2005.
Παραπομπή MLAEckes George. Six Sigma Execution: How to World's Greatest Companies Live and Breathe Six Sigma (sách Photo). In lần thứ 1. American: McGraw-Hill, 2005.
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