Chowdhury, S. (2001). The power of six sigma. Pearson Education Asia.
Lua i Stíl Chicago (17ú heag.)Chowdhury, Subir. The Power of Six Sigma. Delhi: Pearson Education Asia, 2001.
Lua MLA (9ú heag.)Chowdhury, Subir. The Power of Six Sigma. Pearson Education Asia, 2001.
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