Berezansky, Y.M. (1995) “On the 60th birthday of Leonid Pavlovich Nizhnik”, Ukrains’kyi Matematychnyi Zhurnal, 47(10), pp. 1416–1417. Available at: https://umj.imath.kiev.ua/index.php/umj/article/view/5536 (Accessed: 5 December 2025).