QUOIRIN, H. R.; UMEZU, K. An indefinite concave-convex equation under a Neumann boundary condition II. Topological Methods in Nonlinear Analysis, [S. l.], v. 49, n. 2, p. 739–756, 2017. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2017.007. Acesso em: 29 mar. 2024.