1. 1) Altschule, M. D. (1961): Significance of changes in carbohydrate metabolism in schizophrenia. Chemical Pathology of the Nervous System, edited by J. Folch-Pi. Pergamon Press, New York.
2. 2) Bersin, Th. (1963): Biochemie der Mineral- und Spurenelemente. Akademische Verlagsgesellschaft, Frankfurt am Main.
3. 3) Courville, C. B., Nusbaum, R. E., and Butt, E. M. (1962): Trans. Amer. Neurol. Ass., 87, 104.
4. 4) Cumings, J. N. (1965): Trace elements in the brain in health and in neurological disease, Scientific Basis of Medicine, Annual Review.
5. 5) Dixon, M., and E. C. Webb. (1958): Enzymes. Longmans, Green and Co., London.