GORDON JOSEPH M. (2002). SIX SIGMA QUALITY FOR BUSINESS & MANUFACTURE. ELSEVIER.
Lua i Stíl Chicago (17ú heag.)GORDON JOSEPH M. SIX SIGMA QUALITY FOR BUSINESS & MANUFACTURE. AMSTERDAM: ELSEVIER, 2002.
Lua MLA (9ú heag.)GORDON JOSEPH M. SIX SIGMA QUALITY FOR BUSINESS & MANUFACTURE. ELSEVIER, 2002.
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