WASET
    Ngoc Trung Ngo and  Buddhima Indraratna and  Cholachat Rujikiathmakjornr,  Investigating the Shear Behaviour of Fouled Ballast Using Discrete Element Modelling.   journal   = {International Journal of Civil and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    January 2015, vol. 108(12). 1651 - 1655
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/10003377.