1. A. Butts and Ch.D. Coxe:SILVER, Economics, Metallurgy, and Use, Van Nostrand Co. Inc., Princeton, NJ, 1967, pp. 221–26.
2. T.K. Rose and W.A.C. Newman:The Metallurgy of Gold, 7th ed., Met-Chem Research Inc., Boulder, CO, 1937, pp. 47 and 501–03.
3. J.C. Yannopoulus:The Extractive Metallurgy of Gold, Van Nostrand Reinhold, New York, NY, 1991, p. 138.
4. J.L. Bray:Metalurgia Extractiva de los Metales no Ferreos, 2nd ed., Osca S.A., Madrid, 1968, p. 421.
5. D. Proske, H. Blumental, and F. Ensslin:Análisis de Metales, Métodos de Control Industrial, Aguilar, Madrid, 1960, vol. II, p. 641.