1. O. C. Ralston: Electrolytic Deposition and Hydrometallurgy of Zinc, McGraw-Hill, New York, 1921.
2. Liddell: Handbook of Non-ferrous Metallurgy, II, Recovery of the Metals, McGraw-Hill, New York, 1945, pp. 379–443.
3. Mantell: Industrial Electrochemistry, 3rd Edition; McGraw-Hill, New York, 1950, pp. 347–364.
4. Cominco Zinc Department: Can. Min. Jour., May 1954, vol. 75, no. 5, pp. 262–280.
5. K. W. Downes and R. W. Bruce: The Recovery of Elemental Sulphur from Pyrite and Pyrrhotite, Bulletin, Can. Inst. Min. Met., 1955, vol. 48, pp. 127–132.