1. Sherlock, E. B. (1911).The Feeble-Minded. London: Macmillan and Co.
2. Bourneville (1880–1).Arch. Neurol., Paris,1, 81 and 297.
3. Crocker, H. R. (1903).Diseases of the Skin, 2nd ed.
4. Pringle, J. J. (1890).Brit. J. Derm. 2, 1.
5. Bielschowsky, M. andGallus, K. (1913).J. Psychol. Neurol., Lpz.,20, 1.