1. This is the major source of material for this article,1941
2. Kasius RV, ed. The challenge of facts. Selected public health papers of Edgar Sydenstricker. New York: Prodist, 1974.
3. Frost WH. The importance of epidemiology as a function of health departments. Medical Officer (London), 1923;23: 113?4.
4. Frost WH. Epidemiology. Nelson Loose-Leaf System, Public Health-Preventive Medicine. Volume 2, Chapter 7. New York: Thomas Nelson & Sons, 1927. [Reprinted in (1).]
5. Fee E. Disease and discovery. A history of the Johns Hopkins School of Hygiene and Public Health, 1916?1939, Baltimore: The Johns Hopkins Press, 1987.