MATEIKO, Oleg M. Rafail Fedorovich Gabasov. Journal of the Belarusian State University. Mathematics and Informatics, [S. l.], n. 2, p. 115–117, 2020. Disponível em: https://journals.bsu.by/index.php/mathematics/article/view/3179. Acesso em: 17 jul. 2026.