Kal’menov, Tynysbek Sharipovich, and Berikbol Tillabayuly Torebek. “On an Ill-Posed Problem for the Laplace Operator With Nonlocal Boundary Condition”. Eurasian Mathematical Journal 8, no. 1 (March 30, 2017): 50–57. Accessed September 30, 2025. https://emj.enu.kz/index.php/main/article/view/654.