21. Bakeer R. M., Sayed S. M., Cates P., and Subramanian R., 1998, Pullout and shear tests on geogrid reinforced lightweight aggregate, Jour. of Geotextiles and Geomembranes, Vol. 16, pp. 119-133.
25. Hidetoshi Ochiai, Jun Otani, Shigenori Hayashic and Takao Hirai, 1996, The Pull-Out Resistance of Geogrids in Reinforced Soil, Geotextiles and Geomembranes, Vol. 14, pp. 19-42.