Gorbachuk, M.L., Zaderei, P.V., Lukovsky, I.O., Mitropolskiy, Y.A., Romanyuk, A.S., Rukasov, V.I., Samoilenko, A.M., Serdyuk, A.S. and Shevchuk, I.A. 2007. Alexander Ivanovich Stepanets. Ukrains’kyi Matematychnyi Zhurnal. 59, 12 (Dec. 2007), 1722-1724.