1. Aycock, W. L., and G. F. Meadors: The principles of variolation as exemplified by subclinical immunization in poliomyelitis in colder and warmer climates. Amer. J. med. Sci. 215, 296–310 (1948).
2. Casey, A. E., W. J. Fishbein and H. N. Bundesen: Transmission of Poliomyelitis by Patient
3. to Patient Contact. J. Amer. med. Ass. 129, 1141 (1945).
4. Donle, W.: Jahreszeit und Witterung im Seuchengeschehen. Stuttgart: Ferd. Enke 1956.
5. Donle, W.: Beiträge über Poliomyelitis im Weltseuchenatlas. Hamburg: Falk-Verlag, Bd. I: Poliomyelitis in Europa, 1952 Bd. II. Poliomyelitis in Afrika, 1956, Bd. III. Poliomyelitis in der Welt, 1958.