ECKES GEORGE. (2003). SIX SIGMA FOR EVERYONE. JOHN WILEY & SONS, INC.
Lua i Stíl Chicago (17ú heag.)ECKES GEORGE. SIX SIGMA FOR EVERYONE. NEW JERSEY: JOHN WILEY & SONS, INC, 2003.
Lua MLA (9ú heag.)ECKES GEORGE. SIX SIGMA FOR EVERYONE. JOHN WILEY & SONS, INC, 2003.
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