Skorokhodov, D. S. “On the Best Linear Approximation Method for Hölder Classes”. Ukrains’kyi Matematychnyi Zhurnal 67, no. 9 (September 25, 2015): 1265–1284. Accessed April 14, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/2064.