1. Munch;Almkvist, J.;med. Wschr,1911
2. Alpers, B. J. (1928) Arch. Neurol. Psychiat., Chicago, 20, 497.
3. Arnell, R. E., and Guerriero, W. F. (1942) Med. Surg. J., 94, 482.
4. THE BRITISH JOURNAL OF VENEREAL DISEASES;Baker, A.B.;Amer. J. Path,1935
5. Personal communication;Black, D.,1945