ANH, N. D. Short Communication: A technique for investigating nonlinear vibrations. Vietnam Journal of Mechanics, Hanoi, Vietnam, v. 34, n. 2, p. 135–138, 2012. DOI: 10.15625/0866-7136/34/2/928. Disponível em: https://vjs.ac.vn/index.php/vjmech/article/view/928. Acesso em: 7 dec. 2021.