Bich, Dao Huy, Nguyen Dang Bich, and Nguyen Anh Tuan. “On the Solutions of the Mathieu’s Equation”. Vietnam Journal of Mechanics 30, no. 4 (December 31, 2008): 219 – 231. Accessed December 5, 2025. https://vjs.ac.vn/vjmech/article/view/5627.