Mohammed Kadhim, A.-Z., S. K. Ali, and M. Kassim. “Solving Machine Scheduling Problem under Fuzzy Processing Time Using the Simulated Annealing Method”. Journal of Progressive Research in Mathematics, Vol. 14, no. 1, Sept. 2018, pp. 2308-17, http://scitecresearch.com/journals/index.php/jprm/article/view/1605.