RIGGS, J. L. (1897). PRODUCTION SYSTEMS: PLANNING ANALYSIS AND CONTROL. JOHN WILEY.
Lua i Stíl Chicago (17ú heag.)RIGGS, J L. PRODUCTION SYSTEMS: PLANNING ANALYSIS AND CONTROL. NEW-YORK: JOHN WILEY, 1897.
Lua MLA (9ú heag.)RIGGS, J L. PRODUCTION SYSTEMS: PLANNING ANALYSIS AND CONTROL. JOHN WILEY, 1897.
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