BarbirA., Himmelreich Kruli´c K., and PečarićJ. E. “Refinements of Jessen’s Functional”. Ukrains’kyi Matematychnyi Zhurnal 68, no. 7 (July 25, 2016): 879-896. Accessed September 1, 2024. https://umj.imath.kiev.ua/index.php/umj/article/view/1888.