CHABROWSKI, Jan; GIRĀO, Pedro 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: 4 jul. 2025.