LIVREA, Roberto; PAPAGEORGIOU, Nikolaos S.; BARLETTA, Giuseppina. Resonant Neumann equations with indefinite linear part. Topological Methods in Nonlinear Analysis, [S. l.], v. 45, n. 2, p. 469–491, 2015. DOI: 10.12775/TMNA.2015.023. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2015.023. Acesso em: 8 jul. 2025.