Kofanov, V. A., and V. E. Miropol’skii. “On Sharp Kolmogorov-Type Inequalities Taking into Account the Number of Sign Changes of Derivatives”. Ukrains’kyi Matematychnyi Zhurnal 60, no. 12 (December 25, 2008): 1642–1649. Accessed May 3, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/3278.