1. Material requirements planning (MRP) and purchase discounts
2. BENTON , W. C. , and WHYBARK , D. C. , 1979 , Evaluating MRP purchase quantity discount procedures under uncertainty (Discussion paper 138) , School of Business, Indiana University .
3. CALLARMAN , T. E. , WHYBARK , D. C. , 1977 . Purchase quantity discounts in an MRP environment (Discussion paper 72) . School of Business, Indiana University .