1. Measuring of orthodontic forces;Paulich;Am J Orthod Oral Surg,1939
2. A study of applied force as related to use of elastics and coil springs;Bell;Angle Orthod,1951
3. Biophysical properties of orthodontic rubber elastics;Newman;J New Jersey Dent Soc,1963
4. Orthodontic elastic materials;Wong;Angle Orthod,1976
5. Cunningham JS. Coil springs as an application of force;Arnold;Am J Orthod,1934