BEREZANSKY, Yu. M. Mark Grigor’evich Krein. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 46, n. 3, p. 146, 1994. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5752. Acesso em: 6 dec. 2025.