ISOBE, T. Obstructions to the extension problem of Sobolev mappings. Topological Methods in Nonlinear Analysis, [S. l.], v. 21, n. 2, p. 345–368, 2003. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2003.021. Acesso em: 16 apr. 2024.