WU, J. Maslov Index and Quasi-Symplectic Isomorphisms. Contemporary Mathematics, [S. l.], v. 3, n. 2, p. 203–216, 2022. DOI: 10.37256/cm.3220221363. Disponível em: https://ojs.wiserpub.com/index.php/CM/article/view/1363. Acesso em: 8 apr. 2025.