A. S. Ashour AAR and. Free Vibration of Variable Thickness Plates Using Characteristic Orthogonal Polynomial Strip Functions Subjected To Different Combinations of Boundary Conditions. IIUMEJ [Internet]. 2012 Aug. 1 [cited 2024 May 3];2(1). Available from: https://journals.iium.edu.my/ejournal/index.php/iiumej/article/view/338