1. George Tiemann & Co. Surgical Instrument Catalog. New York; 1872:26.
2. Surgical Instruments in Greek and Roman Times;Milne,1907
3. The Vaginal Speculum and its Modifications Throughout the Ages;Ricci,1949
4. Kirkup, J. The Evolution of Surgical Instruments: An Illustrated History from Ancient Times to the Twentieth Century. Novato: historyofscience; 2005:222–223. (A variety of self-retaining retractors for keeping eyelids and jaws pried open had existed for many years; this article refers only to those devices applicable to the thoracic, abdominal, and pelvic cavities).
5. Surgical Instruments, Orthopedic Appliances, Trusses, Etc,1894