1. W. Horwitz (Ed.), Official Methods of Analysis, 12th edn., AOAC, Washington, DC, 1975.
2. K. Heldrich (Ed.), Official Methods of Analysis, 15th edn., AOAC, Washington, DC, 1990.
3. C.A. Watson (Ed.), Official and Standardized Methods of Analysis, 3rd ed., Royal Society of Chemistry, Cambridge, 1994.
4. H. Egan, R.S. Kirk, R. Sawyer, Pearson’s Chemical Analysis of Foods, 8th edn., Churchill Livingstone, Edinburgh, 1981.
5. F.L. Hart, H.J. Firscher, Modern Food Analysis, Springer, New York, 1971.