1. Threshold levels for displacement of human maxillary central incisors in response to lingual directed forces;Lear;J Dent Res,1974
2. Equilibrium theory revisited: factors influencing position of the teeth;Proffit;Angle Orthod,1978
3. Muscle pressures and tooth position: North American Whites and Australian Aborigines;Proffit;Angle Orthod,1975
4. A method of measuring forces acting on the teeth from the lips, cheeks and tongue;Gould;Br Dent J,1962
5. The influence of maximum perioral and tongue force on the incisor teeth;Posen;Angle Orthod,1972