YAN, S. On the number of interior multipeak solutions for singularly perturbed Neumann problems. Topological Methods in Nonlinear Analysis, [S. l.], v. 12, n. 1, p. 61–78, 1998. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.1998.028. Acesso em: 26 apr. 2024.