Audoux B, Bobkov V, Parini E. On multiplicity of eigenvalues and symmetry of eigenfunctions of the $p$-Laplacian. TMNA [Internet]. 2018 Jan. 20 [cited 2024 Jul. 3];51(2):565-82. Available from: https://apcz.umk.pl/TMNA/article/view/TMNA.2017.055