LIN, H.- li; WAG, H.- chiuan; WU, T.- fang. A Palais-Smale approach to Sobolev subcritical operators. Topological Methods in Nonlinear Analysis, [S. l.], v. 20, n. 2, p. 393–407, 2002. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2002.042. Acesso em: 22 jul. 2024.