GOLEV, V. Kiril Popoff - a pioneer of Bulgarian Astronomy. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 98, p. 25–32, 2008. Disponível em: https://stipendii.uni-sofia.bg/index.php/fmi/article/view/126. Acesso em: 22 nov. 2024.