Acu, A.-M., and H. Gonska. “Classical Kantorovich Operators Revisited”. Ukrains’kyi Matematychnyi Zhurnal 71, no. 6 (June 25, 2019): 739-747. Accessed April 26, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/1472.