FRIGON, M.; LEE, J. W. Existence principles for Carathéodory differential equations in Banach spaces. Topological Methods in Nonlinear Analysis, [S. l.], v. 1, n. 1, p. 95–111, 1993. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.1993.009. Acesso em: 24 jul. 2024.