NGUYỄN ĐÔNG ANH; NGUYỄN MINH TRIẾT. Extension of dual criterion to periodic vibrational nonlinear systems. Journal of Technical Education Science, [S. l.], v. 10, n. 3, p. 3–8, 2015. Disponível em: https://www.jte.edu.vn/index.php/jte/article/view/570. Acesso em: 7 apr. 2026.