S.Goel Parveen, Gupta Praveen, & Jain Rajeev. (2004). Six Sigma for Transactions and Service (In lần thứ 1.). American: McGraw -Hill.
Παραπομπή Chicago StyleS.Goel Parveen, Gupta Praveen, και Jain Rajeev. Six Sigma for Transactions and Service. In lần thứ 1. American: McGraw -Hill, 2004.
Παραπομπή MLAS.Goel Parveen, Gupta Praveen, και Jain Rajeev. Six Sigma for Transactions and Service. In lần thứ 1. American: McGraw -Hill, 2004.
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