Jumaa, Hajer A., and Majid Mohammed Abed. “Multiplication Module and Retractable Concept”. Journal of Al-Qadisiyah for Computer Science and Mathematics 15, no. 2 (September 25, 2023): Math Page 14–21. Accessed November 21, 2024. https://jqcsm.qu.edu.iq/index.php/journalcm/article/view/1245.