Berezansky, Yu. M., V. I. Gorbachuk, M. L. Gorbachuk, V. S. Korolyuk, Yu. A. Mitropolskiy, A. M. Samoilenko, and V. G. Tarasov. “On the 60th Birthday of Leonid Pavlovich Nizhnik”. Ukrains’kyi Matematychnyi Zhurnal 47, no. 10 (October 25, 1995): 1416–1417. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/5536.