1. An analysis of tooth color;Clark;Journal of the American Dental Association,1931
2. Color in esthetics;Bergen;New York State Dental Journal,1985
3. Color science and dental art;Preston,1980
4. Shade matching;Miller;Journal of Esthetic Dentistry,1993
5. The value conversion a new concept for expressing the shades of natural teeth;Yamamoto;Quintessence of Dental Technology,1992