1. The modified arrowhead clasp;Adams;Tr. Brit. Soc. Study Orthodont.,1949
2. The modified arrowhead clasp—Some further considerations;Adams;D. Record,1953
3. Possibilities and use of removable labiolingual spring appliances;Crozat;Int. J. Orthodontia,1920
4. The design and construction of fixed orthodontic appliances in stainless steel;Friel;D. Record,1939