1. Operative Dentistry;Black,1908
2. Surgery and Diseases of Mouth and Jaws;Blair,1917
3. Fundamentals of Dental Histology and Embryology;Bödecker,1926
4. Bolk, L. Die überzähligen oberen Inzisivi des Menschen, Deutsche Monat, f. Zahnhk. 35:185-191.
5. Chart of Average Time of Development, Eruption, and Absorption of Teeth;Brady,1924