1. Malocclusion of the Teeth and Fractures of the Maxillae;Angle,1900
2. Indications for the extraction of teeth in orthodontic procedure;Tweed;Am J Orthod,1934
3. A concept of facial esthetics;Peck;Angle Orthod,1970
4. Lip posture and its significance in treatment planning;Burstone;Am J Orthod,1967
5. An esthetic evaluation of lip-teeth relationships present in the smile;Hulsey;Am J Orthod,1970