BILOTSKII, N. N.; BARYSHOVETS, P. P. On groups with a small number of classes of conjugate noncomplemented subgroups. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 62, n. 10, p. 1420–1427, 2010. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/2966. Acesso em: 5 dec. 2025.