1. AASHTO M145.: Classification of soil and soil-aggregate mixtures for highway construction purposes: American Association of State Highway and Transportation Officials (1995).
2. AASHTO T193.: Standard method of test for The California Bearing Ratio: American Association of State Highway and Transportation Officials (1999).
3. AASHTO T208.: Standard method of test for unconfined compressive strength of cohesive soil: American Association of State Highway and Transportation Officials (1992).
4. AASHTO T99.: Standard specification for the moisture-density relations of soils using a 2.5-kg (5.5-lb) rammer and a 305-mm (12-in.) Drop: American Association of State Highway and Transportation Officials (1995).
5. Ali, M., Aziz, M., Hamza, M., Madni, M.F.: Engineering properties of expansive soil treated with polypropylene fibers. Geomechanics and Engineering 22(3), 227–236 (2020). https://doi.org/10.12989/gae.2020.22.3.227