WASET
    Elsa Eka Putri and  N.S.V Kameswara Rao and  M. A. Mannan,  Threshold Stress of the Soil Subgrade Evaluation for Highway Formations.   journal   = {International Journal of Civil and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    August 2012, vol. 68(8). 580 - 586
    [viewed 26 April 2024]. Available from: https://publications.waset.org/pdf/8193.