G.S.Al-Khafaji, Dheia, and Raymond N. Shekoury. “Combinatorial Realizability Of The New Exact Sequence”. Journal of Al-Qadisiyah for Computer Science and Mathematics 2, no. 2 (September 9, 2017): 36–52. Accessed September 20, 2024. https://jqcsm.qu.edu.iq/index.php/journalcm/article/view/222.