Babenko, V. F., and S. A. Selivanova. “On the Connection Between Certain Inequalities of the Kolmogorov Type for Periodic and Nonperiodic Functions”. Ukrains’kyi Matematychnyi Zhurnal 51, no. 2 (February 25, 1999): 147–157. Accessed May 12, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/4594.