MOGILEVSKII, V. I. On generalized rezolvents and characteristic matrices of first-order symmetric systems. Methods of Functional Analysis and Topology, [S. l.], v. 20, n. 4, p. 328–348, 2014. Disponível em: https://zen.imath.kiev.ua/index.php/mfat/article/view/590. Acesso em: 16 dec. 2025.