Al-Hashmi, S. A., and S. K. Nauman. “A Study of Modules over Rings and Their Extensions”. Ukrains’kyi Matematychnyi Zhurnal 70, no. 10 (October 25, 2018): 1299-1312. Accessed May 3, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/1636.