Inayatullah, Syed, Asma Rani, Tanveer Ahmed Siddiqi, Hina Zaheer, Muhammad Imtiaz, and Hafsa Athar Jafree. “An Efficient Method for Pivoting Free Variables in Linear Programming: A Computational Approach”. European Scientific Journal, ESJ 15, no. 9 (March 31, 2019): 1. Accessed September 28, 2020. http://eujournal.org/index.php/esj/article/view/11892.