LAU, A. T.-M.; TAKAHASHI, W. Nonlinear submeans on semigroups. Topological Methods in Nonlinear Analysis, [S. l.], v. 22, n. 2, p. 345–353, 2003. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2003.044. Acesso em: 22 jul. 2024.