Frequency-Domain Approach To Stability And Periodic Solutions Of Certain Fourth-Order Non-Linear Differential Equations. Nonlinear Studies, [S. l.], v. 12, n. 3, 2005. Disponível em: https://www.nonlinearstudies.com/index.php/nonlinear/article/view/230. Acesso em: 15 oct. 2025.