KHANG, N. V.; CAU, T. M. Calculating periodic vibrations of nonlinear autonomous multi-degree-of-freedom systems by the incremental harmonic balance method. Vietnam Journal of Mechanics, Hanoi, Vietnam, v. 26, n. 3, p. 157–166, 2004. DOI: 10.15625/0866-7136/26/3/5700. Disponível em: https://vjs.ac.vn/index.php/vjmech/article/view/5700. Acesso em: 7 dec. 2021.