1. Research Report R84–14;Azzouz A. S.,1984
2. Hvorsley, M. J. 1949.Subsurface exploration and sampling of soils for civil engineering purposes, ASCE Research Project of the Committee on Sampling and Foundation Division 521American Society of Civil Engineers.
3. Static Reference Tests on Piles A1 and A2, Data Report;Karlsrud K.,1981