References
- Kulis, L. H. (1962) The relation between force magnitude and the centre of rotation in the maxillary incisors Thesis, Indiana University School of Dentistry.
- Miller, S. (1966) Rotational axes in human incisor teeth Thesis, University of Oregon Dental School, Portland, Oregon.
- Utley, R. K. (1968) The activity of alveolar bone incident to orthodontic tooth movement American Journal of Orthodontics, 54 (3), 167–201.