SKIBA, Robert. Graph-approximation of multivalued weighted maps. Topological Methods in Nonlinear Analysis, [S. l.], v. 29, n. 1, p. 119–161, 2007. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2007.006. Acesso em: 8 jul. 2025.