1. BALLARD EA. Excessive tearing in infancy and early childhood: The role and treatment of congenital nasolacrimal duct obstruction. Postgraduate Medicine 2000 ; 107 (6) : 149-54
2. Basar E,Qgug H et al. Outcome of office probing and irrigation under topical anesthesia for congenital nasolacrimal duct obstruction. ANN Ophthalmol 2005 ; 37 (2) : 95-98.
3. Becker Anamolies of the lacrimal sac and duct : Atresia of nasolacrimal duct . Duke Elder S: System of Ophthalmology. Normal and Abnormal Developmental Congenital Deformaties,1st edition,Henry Kimpton,London ,1964 ;3 (2) : 936 .
4. Bowman. Diseases of the lacrimal passages. Duke Elder S,MacFaul PA: System of Ophthalmology . The Ocular Adnexa, 1 st edition,Henry Kimpton, London, 1974 ; 13 (2) : 680-81.C
5. Cannizzo. Anomalies of the lacrimal sac and duct: Atresia of the nasolacrimal duct .Duke Elder S: System of Ophthalmology. Normal and Abnormal Developmental Congenital Deformities , Ist edition, Henry Kimpton, London, 1964; 3 (2): 935.
6. Cassady JV. Developmental anatomy of nasolacrimal duct. AMA Arch Ophthalmol 1952 ; 47 : 141-58.
7. Crigler LW. The treatment of congenital dacryocystitis . JAMA 1923 ;81 : 23-4.
8. Dominique Anel . Disease of the lacrimal passage. Duke Elder S, MacFaul PA: System of ophthalmology. The Ocular Adnexa, Ist edition ,Henry Kimpton, London, 1974 ; 13 (2) : 680.
9. Duke Elder. Anomalies of the lacrimal sac and duct: Atresia of nasolacrimal duct. Duke Elder S : System of Ophthalmology. Normal and Abnormal Developmental Congenital Deformaties,1st edition,Henry Kimpton, London ,1964 ;3 (2) : 934.
10. EI- Mansoury J ,Calhoun JH, Nelson LB et al . Results of late probing for congenital nasolacrimal duct obstruction. Ophthalm-ology 1986 ; 93 : 1052-54
11. Ffookes OO. Dacryocystitis in infancy. Br J Ophthalmol 1964 ;46 : 422-34 .
12. Guerry D ,Kendig EL. Congenital impatency of the nasolacrimal duct. Arch Ophthalmol 1948 ;39 : 193 -204.
13. Gupta VP. Paediatric epiphora. Eye Care 2002 : pp.5-11
14. Honavar SG, Prakash VE,Rao GN.Outcome of probing for congenital nasolacrimal duct obstruction in older children. Am J Ophthalmol 2000 ; 130 : 42-8.
15. Jones LT,Wobig JL.Surgery of the eyelids and the lacrimal system. Birmingham, Aesculapius Publishing,1976 : pp 96-104.
16. Kashkouli MB, Beigi B, Parvaresh MM,Kassaee A, Tabatabaee Z. Late and very late initial probing for congenital nasolacrimal duct obstruction ; What is the cause of failure. Br J Ophthalmology 2003;1151: 1-6.
17. Kashkouli MB,Kassaee A, Tabatabaee Z. Initial nasolacrimal duct probing in children under age 5 : Cure rate and factors affecting success. JAAPOS 2002 ; 6(6): 360-63.
18. Katowitz JA,Welsh MG. Timing of initial probing and irrigation in congenital naso-lacrimal duct obstruction. Ophthalmology 1987 ; 94 : 698 -705.
19. Kim YS,Moon SC,Yoo KW .Congenital nasolacrimal duct obstruction : Irrigation or probing ? Korean J Ophthalmol 2000 ; 14( 2) : 90-6.
20. Koke MP.Treatment of occluded nasolacrimal ducts in infants. Arch Ophthalmol 1950; 43: 750-54.
21. Kushner BJ . Congenital nasolacrimal duct obstruction. Arch Ophthalmol 1982; 100: 597-600.
22. Kushner BJ. The management of nasolacrimal duct obstruction in children between 18 months and 4 years old. JAAPOS 1998 ; 2(1) : 57-60.
23. MacEwen CJ. . Congenital nasolacrimal duct obstruction. Comprehensive Ophtha-lmology Update 2006 ; 7(2): 79-87.
24. MacEwen CJ,Young JDH,Barras CW et al. Value of nasal endoscopy and probing in the diagnosis and management of children with Congenital epiphora . Br J Ophthalmol 2001 ; 85:314-18.
25. Maheshwari R. Results of probing for congenital nasolacrimal duct obstruction in children older than 13 months of age.Indian J Ophthalmol 2005 ; 53 : 49-51.
26. Mannor GE,Rose GE,Frimpong-Ansah Ket al.Factors affecting the success of nasolacrimal duct probing for congenital nasolacrimal duct obstruction. Am J Ophthalmology 1999 ; 127: 616-17.
27. Peterson RA , Robb RM.The natural course of congenital obstruction of the nasolacrimal duct. J Paediatric Ophthalmol Strabismus 1978 ; 15:246-50.
28. Robb RM. Probing and irrigation for congenital nasolacrimal duct obstruction .Arch Ophthalmol 1986 ; 104 : 378-79.
29. Robb RM.Success rates of nasolacrimal duct probing at time interval after 1 year of age. Ophthalmology 1998 ; 105 : 1306-10.
30. Stager D,Baker JD,Frey T,Weakley R,Birch EE Jr.Office probing of congenital nasolacrimal duct obstruction . Ophthalm-ology Surgery 1992 ; 23 : 482-84.
31. Sturrock SM,MacEwen CJ,Young JDH. Long – term results after probing for congenital nasolacrimal duct obstruction. Br J Ophthalmol 1994 ; 78 : 892-94.
32. Zwann J. Treatment of congenital nasolacrimal duct obstruction before and after the age of 1 year Ophthalmology and Surgery and Lasers 1997 ; 28 : 932-36.