3Kashkouli MB, Beigi B, Parvaresh MM, et a/.Late and wery late initial probing for congenital nasolacrimal duct obstruc- tion : what is the cause of failure [ J ]. Br J Ophthalmol, 2003 ; 87(9) :1151-1153.
4Singh Bhinder G, Singh Bhinder H. Repeated probing results in the treatment of congenital nasolacrima] duct obstruction [ J ]. Eur J Ophthalmol, 2004,14 ( 3 ) : 185-192.