M. Azizov, “Information Complexity of Multidimensional Fredholm Integral Equations with Harmonic Coefficients”, Ukr. Mat. Zhurn., vol. 52, no. 7, pp. 867–874, Jul. 2000, Accessed: Apr. 13, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/4485