1. F. H. Habashi:Extractive Metallurgy, Gordon and Breach Science Publishers, Inc., New York, NY, 1969, pp. 227–41.
2. R.D. Pehlke:Unit Process of Extractive Metallurgy, American Elsevier Publishing Co., New York, NY, 1975, pp. 224–25.
3. G. W. Castellan:Physical Chemistry, 2nd ed., Addison-Wesley Publishing Co., Reading, MA, 1972, pp. 711–12.
4. David R. Gaskell:Introduction to Metallurgical Thermodynamics, McGraw-Hill Kogakusha Ltd., 1973, pp. 471-74.
5. F. H. Habashi:Extractive Metallurgy, Gordon and Breach Science Publishers, Inc., New York, NY, 1969, pp. 51–53.