1. Os penis in man and beast;Bett;Ann. Roy. Coll. Surg., Engl.,1952
2. A case of a genuine penis bone in aman;Binstorfer;Klin. Med. (Wien),1960
3. Occurrence of bone tissue in the human penis;Eglitis;J. Urol.,1953
4. Os penis;Elliott;J. Urol.,1962
5. On the formation of bone in the human penis;Gerster,1913