1. Human facial types—Facial expression;McKenzie;Dental Cosmos,1935
2. Esthetics and its relation to orthodontic therapy;Reidel;Angle Orthodontist,1950
3. Survival of the periodontium during and after orthodontic treatment;Stallard;Am. J. Orthodontics,1964
4. Simulation of natural appearance;Krajicek;J. Pros. Dent.,1962