1. Seventy-fourth annual session of the American Dental Association;Clark,1932
2. A survey of color education in the dental schools of the world. El Paso, Tex;Sproull;U.S. Army Research report,1967
3. Color matching in dentistry. Part I: The threedimensional nature of color;Sproull;J Prosthet Dent,1973
4. The Size of Acceptable Color Differences
5. Shades of meaning;Little;Color Engineering,1969