1. Appleton, J.T.L.: Bacterial Infection, With Special Reference to Dental Practice, ed. 4, London, 1950, Henry Kimpton, pp. 409-410.
2. Rosebury, T.: The Bacteriology of Mucous Membranes in Bacterial and Mycotic Infections of Man, ed. 2, ed. Dubos, R., Philadelphia, 1952, J. B. Lippincott Co., pp. 694-695.