Saeed Delara and  Kendra MacKay,  A Comparison between Russian and Western Approach for Deep Foundation Design.   journal   = {International Journal of Geotechnical and Geological Engineering}, [online]. World Academy of Science, Engineering and Technology.
    April 2019, vol. 149(5). 267 - 274
    [viewed 23 November 2019]. Available from: https://publications.waset.org/pdf/10010308.