BabenkoV. F., and LigunA. A. “Some Bernstein-Type Inequalities for Trigonometric Polynomials”. Ukrains’kyi Matematychnyi Zhurnal 45, no. 3 (March 25, 1993): 428–430. Accessed November 24, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/5825.