F. G. Abdullayev and M. Küçükaslan, “On the Convergence of Fourier Series with Orthogonal Polynomials inside and on the Closure of a Region”, Ukr. Mat. Zhurn., vol. 54, no. 10, pp. 1299–1312, Oct. 2002, Accessed: Apr. 09, 2025. [Online]. Available: https://umj.imath.kiev.ua/index.php/umj/article/view/4169