Butsan , G.P. and Lyatambur , K.N. (1988) “Primary multiplicative systems of almost linear operators for almost linear additive operator system without continuity conditions”, Ukrains’kyi Matematychnyi Zhurnal, 40(6), pp. 717–724. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/9280 (Accessed: 6 December 2025).