A. N. Urumbaev, “On the optimization of direct methods for solving fredholm integral equations of the second kind with infinitely smooth kernels”, Ukr. Mat. Zhurn., vol. 45, no. 12, pp. 1695–1701, Dec. 1993, Accessed: Apr. 09, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/5978