1. Malocclusion of the Teeth;Angle,1907
2. Fundamental Principles of a Systematic Diagnosis of Dental Anomalies;Simon,1926
3. The Face and Occlusion of the Teeth in Man;Hellman;Int. J. Orthodontia,1927
4. Some Biologic Aspects: Their Implications and Application in Orthodontic Practice;Hellman;Int. J. Orthodontia,1937
5. A Preliminary Study in Development as It Affects the Human Face;Hellman;Dental Cosmos,1927