“On the Correctness of One Class of Fourth Order Singular Differential Equations”. ҚазҰУ Хабаршысы. Математика, механика, информатика сериясы 123, no. 3 (October 12, 2024): 21–32. Accessed July 14, 2026. https://bm.kaznu.kz/index.php/kaznu/article/view/1516.