1. Human Embryology (Prenatal Development of Form and Function);Hamilton, W.J.; Boyd, J.D.; Mossman, H.W.,1945
2. Horwitz, T. (1941). Arch. Path. (Chicago), 31, 354.
3. Kernohan, J. W. (1941). Ibid., 32, 843.
4. Masson, P. (1932). Amer. J. Path., 8, 367.
5. Quoted by Penfield, W., in Tumours of the Sheaths of the Nervous System in Cytology and Cellular Pathology of the Nervous System. Vol. III;Mallory;Ibid,1920