DIMASSI, Mouez; ZERZERI, Maher. Spectral shift function for slowly varying perturbation of periodic Schrödinger operators. CUBO, A Mathematical Journal, [S. l.], v. 14, n. 1, p. 29–47, 2012. DOI: 10.4067/S0719-06462012000100004. Disponível em: https://cubo.ufro.cl/index.php/cubo/article/view/1352. Acesso em: 12 oct. 2025.