KUPERBERG, Krystyna M.; KUPERBERG, Włodzimierz; MINC, Piotr; REED, Coke S. Examples related to Ulam’s fixed point problem. Topological Methods in Nonlinear Analysis, [S. l.], v. 1, n. 1, p. 173–181, 1993. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.1993.013. Acesso em: 8 jul. 2025.