BRACHO, J.; CLAPP, M.; MARZANTOWICZ, W. Symmetry breaking solutions of nonlinear elliptic systems. Topological Methods in Nonlinear Analysis, [S. l.], v. 26, n. 1, p. 189–201, 2005. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2005.030. Acesso em: 23 apr. 2024.