KOVALENKO, V. I. Structure of finite nondispersible groups each nonmetacyclic subgroup of which is normal. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 48, n. 10, p. 1337–1341, 1996. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5219. Acesso em: 14 apr. 2025.