GRANAS, A. On the Leray-Schauder alternative. Topological Methods in Nonlinear Analysis, [S. l.], v. 2, n. 2, p. 225–231, 1993. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.1993.040. Acesso em: 22 jul. 2024.