1. The six keys to normal occlusion;Andrews;Am J Orthod,1972
2. The maxillary first permanent molar as a causative factor in arch length deficiency;Foresman;Angle Orthod,1964
3. Nonextraction treatment;Cetlin;J Clin Orthod,1983
4. Relationship of the maxilary first molar in normal occlusion and malocclusion;Henry;Am J Orthod,1956
5. Determination of the angle of rotation of the upper first molar to the median raphe of the palate in different types of malocclusion;Friel;Dent Pract,1959