STEPANETS, O. I.; SHYDLICH, A. L. On some properties of convex functions. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 59, n. 7, p. 920–938, 2007. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/3357. Acesso em: 5 dec. 2025.