Ali Ghodsbin Jahromi and  Ehsan Moradi,  Study of the Effect of Soil Compaction and Height on Pipe Ovality for Buried Steel Pipe.   journal   = {International Journal of Aerospace and Mechanical Engineering}, [online]. World Academy of Science, Engineering and Technology.
    January 2020, vol. 157(1). 43 - 52
    [viewed 27 April 2024]. Available from: https://publications.waset.org/pdf/10011027.