فهرس المقالات Multi-objective mixed-integer nonlinear programming حرية الوصول المقاله صفحة الملخص نص كامل 1 - Multiple Items Supplier Selection, Economic Lot-sizing, and Order Allocation Under Quantity Discount: A Genetic Algorithm Approach Getachew Basa Bonsa Till Becker Abdelkader Kedir 10.22094/joie.2023.1901314.1751