DINH, N. V. Stability of a parametrically - excited system under two excitations. Vietnam Journal of Mechanics, Hanoi, Vietnam, v. 15, n. 2, p. 27–31, 1993. DOI: 10.15625/0866-7136/10199. Disponível em: https://vjs.ac.vn/index.php/vjmech/article/view/10199. Acesso em: 2 may. 2024.