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2. 1996. An illustrated history of medicine. London: Tiger Books International. p 18-19.
3. Dorland's Illustrated Medical Dictionary. 1965. 24th Ed. Philadelphia: W.B. Saunders Co. p 1670.
4. 1929. An introduction to the history of medicine, 4th Ed. Philadelphia: W.B Saunders Co. p 114-115.
5. From Galen to Gutzmann?Hans von Leden (http://www.mh-hannover.de/service/uep/Region/Europe/Germany/ST/Galen.htm).