AL-JAWARY, Majeed; ABD- AL- RAZAQ, Sayl. Analytic and numerical solution for duffing equations. International Journal of Basic and Applied Sciences, [S. l.], v. 5, n. 2, p. 115–119, 2016. DOI: 10.14419/ijbas.v5i2.5838. Disponível em: https://www.sciencepubco.com/index.php/ijbas/article/view/5838.. Acesso em: 24 may. 2024.