HRYSHCHENKO, O. Yu.; KLYUSHIN, D. A.; LYASHKO, S. I.; SERGIENKO, I. V. Ivan Ivanovych Lyashko (on his 90 th birthday). Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 64, n. 11, p. 1568–1571, 2012. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2681. Acesso em: 6 dec. 2025.