1. Special Procedure for Testing Soil and Rocks for Engineering Purposes (D422-54);ASTM (American Society of Testing Materials),1970
2. Standard Test Method for Specific Gravity of Soils;ASTM,1999
3. The Nature and Properties of Soils;Brady,2002
4. Cameron, R.E., 1992. Guide to Site and Soil Description for Hazardous Waste Site Characterization. Metals. vol. 1. EPA/600/4-91/029.
5. Specific surface;Carter,1986