KUPIN, S.; GOLINSKII, L. On complex perturbations of infinite band Schrödinger operators. Methods of Functional Analysis and Topology, [S. l.], v. 21, n. 3, p. 237–245, 2015. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/614. Acesso em: 4 feb. 2026.