Boutahar Lhoucine and  El Bikri Khalid and  Benamar Rhali,  Geometrically Non-Linear Axisymmetric Free Vibration Analysis of Functionally Graded Annular Plates.   journal   = {International Journal of Aerospace and Mechanical Engineering}, [online]. World Academy of Science, Engineering and Technology.
    November 2013, vol. 83(11). 2290 - 2299
    [viewed 19 September 2024]. Available from: https://publications.waset.org/pdf/9996643.