WASET
    M. R.Isvandzibaei and  A.Jahani,  Vibration of Functionally Graded Cylindrical Shells under Effects Free-free and Clamed-clamped Boundary Conditions.   journal   = {International Journal of Mechanical and Mechatronics Engineering}, [online]. World Academy of Science, Engineering and Technology.
    September 2010, vol. 45(9). 800 - 805
    [viewed 23 April 2024]. Available from: https://publications.waset.org/pdf/14025.