1. Anatomy of the Root Apex in Relation of Treatment Problems;Collidge;J. Amer. Dent. Ass,1929
2. Filling Root Canals in Three Dimensions;Schilder;Dent. Clin. N. Amer,1967
3. Endodontic Practice;Grossman,1965
4. Endodontics;Ingle,1965
5. The Anatomy of the Root Canals of the Teeth of the Permanent Dentition;Hess,1925