Tossaporn Kachanubal and  Somkait Udomhunsakul,  Rock Textures Classification Based on Textural and Spectral Features.   journal   = {International Journal of Geotechnical and Geological Engineering}, [online]. World Academy of Science, Engineering and Technology.
    March 2008, vol. 15(3). 658 - 664
    [viewed 09 August 2020]. Available from: https://publications.waset.org/pdf/8816.