GANCHEV, I. 110 Anniversary of the Faculty of Mathematics and Informatics at the Sofia University "St. Kl. Ohridski" (in Bulgarian). Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 93, p. 5–24, 2001. Disponível em: https://stipendii.uni-sofia.bg/index.php/fmi/article/view/198. Acesso em: 4 dec. 2024.