1. R. Bock, A Handbook for Decomposition Methods in Analytical Chemistry (translated by I.L. Marr), International Textbook Co., Glasgow, UK, 1979.
2. P.G. Jeffery, D. Hutchinson, Chemical Methods of Rock Analysis, 3rd Edition, Pergamon Press, Oxford, 1981.
3. Methods Used and Adopted by Association of Florida Phosphate Chemists, 7th Edition, Bartow, FL, 1991.
4. Rapid procedure for the dissolution of a wide variety of ore and smelter samples prior to analysis by inductively coupled plasma atomic emission spectrometry