AUDOUX, B.; BOBKOV, V.; PARINI, E. On multiplicity of eigenvalues and symmetry of eigenfunctions of the $p$-Laplacian. Topological Methods in Nonlinear Analysis, [S. l.], v. 51, n. 2, p. 565–582, 2018. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2017.055. Acesso em: 19 apr. 2024.