1. Beutler, E., V. F. Fairbanks, and J. L. Fahey: Clinical Disorders of Iron Metabolism. New York-London: Grune and Stratton 1963.
2. Frazer, J. G.: The Golden Bough: The Magic Art and the Evolution of Kings, [p. 158.] New York: MacMillian Co. 1935.
3. Gruner, D. C.: Treatise on the Canon of Medicine of Avicenna. London: Luzak 1930.
4. Blaud, P.: Rev. Med. Franc. 'Etrang. 45, 341 (1832).
5. Goodwin, H.: Z. Physik. Chem. 21, 1 (1896).