WASET
    M. Mahdi and  N. Shariatmadari,  Construction Procedures Evaluation of Three Adjacent Tunnels and Excavation Step Effects.   journal   = {International Journal of Civil and Environmental Engineering}, [online]. World Academy of Science, Engineering and Technology.
    January 2014, vol. 85(1). 86 - 90
    [viewed 24 April 2024]. Available from: https://publications.waset.org/pdf/9997484.