D’APRILE, T. An eigenvalue semiclassical problem for the Schrödinger operator with an electrostatic field. Topological Methods in Nonlinear Analysis, [S. l.], v. 27, n. 1, p. 149–175, 2006. Disponível em: https://apcz.umk.pl/TMNA/article/view/TMNA.2006.006. Acesso em: 20 apr. 2024.