Bodenchuk, V. V., and A. S. Serdyuk. “Exact Values of Kolmogorov Widths for the Classes of Analytic Functions. I”. Ukrains’kyi Matematychnyi Zhurnal 67, no. 6 (June 25, 2015): 719–738. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/2017.