Davуdоv E. G. On the graph groups of groups of automorphisms of finite graphs . Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 18, n. 6, p. 111–115, 1966. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/8465. Acesso em: 6 dec. 2025.