1. Ryle J: The Natural History of Disease. London, Oxford University Press, 1936.
2. Osier W: Evolution of Modern Medicine. New Haven, Yale University Press, 1921.
3. Adams F: The Genuine Works of Hippocrates. London, Sydenham Society, 1849.
4. Bacon F: Selected Writings. New York, Random House Inc., 1955.
5. Sydenham T: Quoted by F. Kraüpl Taylor. In: The Concepts of Illness, Disease and Morbus. England, Cambridge University Press, 1979.