CHABROWSKI, J.; GIRĀO, P. M. Symmetric solutions of the Neumann problem involving a critical Sobolev exponent. Topological Methods in Nonlinear Analysis, [S. l.], v. 19, n. 1, p. 1–27, 2002. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2002.001. Acesso em: 22 lip. 2024.