1. P.A. Laxen:Hydrometallurgy, 1984, vol. 13, pp. 169–92.
2. A.W. Allen:Metall. Chem. Eng., 1918, vol. 18 (12), pp. 642–44.
3. J. Gross and J.W. Scott: Technical Paper No. 378, U.S. Bureau of Mines, Washington, DC, 1927.
4. V.A. Garten and D.E. Weiss:Rev. Pure Appl. Chem., 1957, vol. 7, pp. 69–121.
5. I.N. Plaskin:Metallurgy of Noble Metals, Metallurgizolat, 1958.