SHARKO, V. V. The Mors numbers and minimal Mors functions on the non-singly-connected manifolds . Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 40, n. 1, p. 130–131, 1987. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/9072. Acesso em: 5 dec. 2025.