ARTEMOVICH, O. D. On locally graded groups with minimality condition for a certain system of nonhypercentral subgroups. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 51, n. 10, p. 1425–1430, 1999. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4742. Acesso em: 11 apr. 2025.