1. The Orders of Mammals;Gregory;Bull. Am. Museum of Natural History,1910
2. The Origin and Evolution of the Human Dentition;Gregory,1922
3. Palaeontology of the Human Dentition;Gregory,1926
4. Factors Influencing Occlusion;Hellman;Angle Orthodontist,1942
5. The Dentition of Dryopithecus and the Origin of Man;Gregory,1926