1. Clinically Oriented Anatomy;Moore,1980
2. Anatomy: A Regional Atlas of the Human Body;Clemente,1981
3. Synopsis of Ano-Rectal Diseases;Hirschman,1942
4. Anorectal disorders;Janicke;Emerg Med Clin North Am,1996
5. Anal fissures and fistulas;Goldstein;Postgrad Med,1987