NikodemK., and RajbaT. “Ohlin and Levin-Stečkin-Type Results for Strongly Convex Functions”. Annales Mathematicae Silesianae, Vol. 34, no. 1, July 2020, pp. 123-32, https://www.journals.us.edu.pl/index.php/AMSIL/article/view/13637.