AIZICOVICI, Sergiu; PAPAGEORGIOU, Nikolaos S.; STAICU, Vasile. Resonant nonlinear periodic problems with the scalar $p$-Laplacian and a nonsmooth potential. Topological Methods in Nonlinear Analysis, [S. l.], v. 27, n. 2, p. 269–288, 2006. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2006.011. Acesso em: 8 jul. 2025.