Savchuk, V. V., M. V. Savchuk, and S. O. Chaichenko. “Approximation of Bounded Holomorphic and Harmonic Functions by Fejér Means”. Ukrains’kyi Matematychnyi Zhurnal 71, no. 4 (April 25, 2019): 516–542. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/1455.