Yeshkeyev, A.R., and A.K. Issayeva. “∇-Cl-Atomic and Prime Sets”. Bulletin of the Karaganda University. Mathematics Series 93, no. 1 (March 30, 2019): 88–94. Accessed September 7, 2025. http://mts.buketov.edu.kz/index.php/mathematics-vestnik/article/view/281.