ROSTAMANI, M.; HEJAZIAN, S. Maps preserving Fredholm or semi-Fredholm elements relative to some ideal. CUBO, A Mathematical Journal, [S. l.], v. 17, n. 1, p. 29–40, 2015. DOI: 10.4067/S0719-06462015000100003. Disponível em: https://www.perspectivasdelacomunicacion.cl/ojs/index.php/cubo/article/view/1149. Acesso em: 19 may. 2024.