1. Access openings and tooth morphology. Pathways of the pulp;Burns,1984
2. Endodontic therapy;Weine,1982
3. Incidence of bifurcated root canals in mandibular bicuspids;Amos;J Am Dent Assoc,1955
4. Mandibular premolars with more than one root canal in different race groups;Trope;J Endodon,1986
5. Sicher's oral anatomy;DuBrul,1980