Salehi M, Rezaei H. A Fuzzy Multi-Objective Model for Allocating Orders to Suppliers Under Shortfall and Price-Quantity Discounts: An MPSO and NSGA-II with Tuned Parameters. IJIEPR 2019; 30 (2) :225-239 URL: http://ijiepr.iust.ac.ir/article-1-731-en.html