Anh, Le Thi Ngoc, Vu Thi An Ninh, Tran Van Lang, and Nguyen Dinh Kien. “Free Vibration of Bidirectional Functionally Graded Sandwich Beams Using a First-Order Shear Deformation Finite Element Formulation”. Journal of Science and Technology in Civil Engineering (JSTCE) - HUCE 14, no. 3 (August 19, 2020): 136–150. Accessed September 18, 2026. https://stce.vjst.net/index.php/en/article/view/1746.