S. G. Solodkii, “Complexity of fredholm equations of the second kind with kernels from anisotropic classes of differentiable functions”, Ukr. Mat. Zhurn., vol. 48, no. 4, pp. 525–532, Apr. 1996, Accessed: Apr. 13, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/5315