1. Abu Ajamieh M (1980) An assessment of the El-Lajjun oil shale deposit. Internal report, NRA
2. ASTMD2487-00 (2000) Standard classification of soils for engineering purposes (Unified Soil Classification System). ASTM International
3. ASTM D422-63 (2002) Standard test method for particle-size analysis of soils ASTM International
4. ASTM D 4318 (2003) Standard test methods for liquid limit, plastic limit, and plasticity index of soils (D4318-00), American Society for Testing and Materials
5. ASTM D 698-00 (2000) Standard test methods for laboratory compaction characteristics of soil using standard effort (12,400 ft-lbf/ft3 (600 kN-m/m3))