WASET
    S. Hellam and  Y. Oulahrir and  F. El Mounchid and  A. Sadiq and  S. Mbarki,  3D Objects Indexing with a Direct and Analytical Method for Calculating the Spherical Harmonics Coefficients.   journal   = {International Journal of Computer and Information Engineering}, [online]. World Academy of Science, Engineering and Technology.
    July 2015, vol. 98(2). 613 - 623
    [viewed 27 April 2024]. Available from: https://publications.waset.org/pdf/10001825.