1. Butlin, Henry T. (1889). St. Bart's Hosp. Rep., 25, 193.
2. Butlin, Henry T. (1892). Brit. med. J., 1, 1341; 2, 1, 66.
3. Earle, H. (1823). Med. -Chir. Trans., 12, 296.
4. Cancer of the Scrotum in Relation to Occupation;Henry, S.A.,1946
5. Oxford University Press, London. Horder, Thomas J. (1894). St. Bart's Hosp. Rep., 30, 163.