Gupta,P.K, & Hira,D.S. (1991). Problems in Operations Research: Principles and solutions. S.Chand & company Ltd.
Chicago Style aipamenaGupta,P.K, and Hira,D.S. Problems in Operations Research: Principles and Solutions. New Delhi: S.Chand & company Ltd, 1991.
MLA aipamenaGupta,P.K, and Hira,D.S. Problems in Operations Research: Principles and Solutions. S.Chand & company Ltd, 1991.
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