Editorial Board. “Mstislav Vsevolodovich Keldysh (On His 60th Birthday) ”. Ukrains’kyi Matematychnyi Zhurnal 23, no. 2 (February 23, 1971): 218–220. Accessed December 5, 2025. https://umj.imath.kiev.ua/index.php/umj/article/view/8503.