AIZICOVICI, S.; PAPAGEORGIOU, N. S.; STAICU, V. Nonlinear periodic system with unilateral constraints. Topological Methods in Nonlinear Analysis, [S. l.], v. 54, n. 2B, p. 871–885, 2019. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2019.062. Acesso em: 22 lip. 2024.