HAYAT, Umer, Abid KAMRAN, Ambreen BIBI, Ahmet YILDIRIM, and Syed Tauseef MOHYUD-DIN. 2013. “On System of Time-Fractional Partial Differential Equations”. Walailak Journal of Science and Technology (WJST) 10 (5):437-48. https://wjst.wu.ac.th/index.php/wjst/article/view/317.