Vakarchuk, S. B. “On Some Extremal Problems of Approximation Theory in the Complex Plane”. Ukrains’kyi Matematychnyi Zhurnal 56, no. 9 (September 25, 2004): 1155-1171. Accessed May 6, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/3832.