NAJAFI, M.; MOGHIMI, M.; MASSAH, H. Analytical treatment for nonlinear oscillation equations and vibratory system of waves. Tamkang Journal of Mathematics, [S. l.], v. 40, n. 1, p. 77–94, 2009. DOI: 10.5556/j.tkjm.40.2009.38. Disponível em: https://journals.math.tku.edu.tw/index.php/TKJM/article/view/38. Acesso em: 3 may. 2024.