ROUSSEVA, A. On the subplanes of the Hughes planes of odd square prime order. Ann. Sofia Univ. Fac. Math. and Inf., [S. l.], v. 92, p. 65–72, 2000. Disponível em: https://stipendii.uni-sofia.bg/index.php/fmi/article/view/255. Acesso em: 23 nov. 2024.