Orbital Instability of Standing Waves for the Coupled Nonlinear Klein-Gordon Equations. Journal of Partial Differential Equations, [S. l.], v. 21, n. 4, p. 303–314, 2020. Disponível em: https://global-sci.com/index.php/jpde/article/view/4125. Acesso em: 5 dec. 2025.