1.Dong DT, Dung DV. Nonlinear vibration of functionally graded material sandwich doubly curved shallow shells reinforced by FGM stiffeners. Part 1: Governing equations. Vietnam J. Mech. [Internet]. 2017 Sep. 23 [cited 2025 Dec. 5];39(3):245-57. Available from: https://vjs.ac.vn/vjmech/article/view/9692