Khazaei, J. ., and A. . Eslami. “Geotechnical Behavior of Helical Piles Via Physical Modeling by Frustum Confining Vessel (FCV)”. International Journal of Geography and Geology, vol. 5, no. 9, June 2016, pp. 167-81, doi:10.18488/journal.10/2016.5.9/10.9.167.181.