LIMAN , F. N. Groups whose all infinite Abelian pd-subgroups are normal. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 44, n. 6, p. 796–800, 1992. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8011. Acesso em: 6 dec. 2025.