Barbir, A., Himmelreich, K. K. and Pečarić, J. E. (2016) “Refinements of Jessen’s functional”, Ukrains’kyi Matematychnyi Zhurnal, 68(7), pp. 879-896. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/1888 (Accessed: 20April2024).