VÄTH, M. Fixed point theorems and fixed point index for countably condensing maps. Topological Methods in Nonlinear Analysis, [S. l.], v. 13, n. 2, p. 341–363, 1999. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.1999.018. Acesso em: 28 mar. 2024.