An Application of He’s Variational Iteration Method for Solving Duffing - Van Der Pol Equation. AL-Rafidain Journal of Computer Sciences and Mathematics, [S. l.], v. 10, n. 2, p. 153–163, 2013. DOI: 10.33899/csmj.2013.163482 . Disponível em: https://csmj.uomosul.edu.iq/index.php/csmj/article/view/36468. Acesso em: 25 jun. 2026.