MARTIO, O.; SARVAS, J. Injectivity theorems in plane and space. Annales Fennici Mathematici, [S. l.], v. 4, n. 2, p. 383–401, 1979. DOI: 10.5186/aasfm.1978-79.0413. Disponível em: https://afm.journal.fi/article/view/134362. Acesso em: 26 apr. 2025.