1. Molar distalization by intraoral force application;Jeckel;Eur J Orthod,1991
2. Orthodontics—force or persuasion;Kloehn;Angle Orthod,1953
3. Cephalometric analysis and synthesis;Ricketts;Angle Orthod,1961
4. Ricketts RM. Features of bioprogressive therapy: factors in headgear design and application. Rocky Mountain Orthodontics Communicator, Denver, Colo; 1973:27-31.
5. Planning treatment on the basis of the facial pattern and an estimate of its growth;Ricketts;Angle Orthod,1957