Goldratt, E. M. (2006). Necessary but not Sufficient. Productivity and Quality Pub-Madras.
Lua i Stíl Chicago (17ú heag.)Goldratt, Eliyahu M. Necessary but Not Sufficient. Productivity and Quality Pub-Madras, 2006.
Lua MLA (9ú heag.)Goldratt, Eliyahu M. Necessary but Not Sufficient. Productivity and Quality Pub-Madras, 2006.
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