SHARKO, V. V. Topological aspects of dynamical systems on manifolds. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 45, n. 6, p. 876–878, 1993. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/5878. Acesso em: 5 dec. 2025.