1. Gale T.Electricity, or ethereal fire considered. Troy, NY: Moffitt & Lyon, 1802:75
2. Brecher R, Brecher E.The rays: a history of radiology in the United States and Canada.Baltimore, MD: Williams & Wilkins, 1969: 16-23
3. Inauguration of radiotherapy as a new scientific speciality by Leopold Freund 100 years ago
4. Williams FH.The Roentgen rays in medicine and surgery. New York, NY: MacMillan Co.1901
5. Pusey WA.Rontgen rays in therapeutics and diagnosis.Philadelphia, PA: Saunders,1903