Qi, Feng, XiBo-Yan, and ZhangTian-Yu. “Hermite–Hadamard-Type Integral Inequalities for Functions Whose First Derivatives Are Convex”. Ukrains’kyi Matematychnyi Zhurnal 67, no. 4 (April 25, 2015): 555-567. Accessed July 27, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/2002.