KAPLUN, Yu. I.; SAMOILENKO, V. G. Existence and Extendability of Solutions of the Equation $g(t, x) = 0$. Ukrains’kyi Matematychnyi Zhurnal, [S. l.], v. 53, n. 3, p. 372–382, 2001. Disponível em: https://umj.imath.kiev.ua/index.php/umj/article/view/4259. Acesso em: 6 dec. 2025.