LANGER, H.; LANGER, M.; SASVÁRI, Z. Continuations of Hermitian indefinite functions and corresponding canonical systems: an example. Methods of Functional Analysis and Topology, [S. l.], v. 10, n. 1, p. 39–53, 2004. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/230. Acesso em: 17 dec. 2025.