1. Allison, F.E. (1973). Soil Organic Matter and its Role in Crop Production. Elsevier Sci. Publ. Co. (Amsterdam), 673 p.
2. Can We Expect a Consistent Efficiency of Municipal Waste Compost Application?
3. Richards, L.A. (Ed.), (1954). Diagnosis and Improvement of Saline and Alkaline Soils. U.S. Dept. of Agriculture, Handbook No. 60, Washington D.C. 160 p.