DRÁBEK, P.; LANGEROVÁ, M. On the second order equations with nonlinear impulses - Fredholm alternative type results. Topological Methods in Nonlinear Analysis, [S. l.], v. 44, n. 1, p. 249–261, 2016. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2014.046. Acesso em: 20 apr. 2024.