LUDKOVSKY, S.V. Wrap groups of fiber bundles and their structure. CUBO, A Mathematical Journal, [S. l.], v. 11, n. 1, p. 101–121, 2009. Disponível em: https://cubo.ufro.cl/index.php/cubo/article/view/1481. Acesso em: 12 oct. 2025.