List of Articles optimal solution Open Access Article Abstract Page Full-Text 1 - On characterizing efficient and properly efficient solutions for multi- objective programming problems in a complex space Hamiden Abd Elwahed Alhanouf Alburaikan Florentin Smarandache 10.22094/joie.2023.1972093.2003 Open Access Article Abstract Page Full-Text 2 - A new approach to solving multi-follower multi-objective linear bilevel programming problems Habibe Sadeghi Farzaneh Anis Hosseini 10.22094/joie.2022.543647.1512 Open Access Article Abstract Page Full-Text 3 - Building a Multi-Objective Model for Multi-Product Multi-Period Production Planning with Controllable Processing Times: A Real Case Problem Mir Bahadorgholi Aryanezhad Mehdi Karimi-Nasab Seyed Mohammad Taghi Fatemi Ghomi