1. Bennett, J.E. The lacrimal drainage system. In: T.D. Duane, ?Clinical Ophthalmology?, vol. 5 chapt. 11. Hagerstown, Harper & Row, 1976.
2. Busse, H. & Hollwich, F. Erworbene Stenosen. In: ?Erkrankungen der ableitende Tränenwege und ihre Behandlung?. Stuttgart, Enke, 1978, p. 119?126.
3. Jones, L.T. & Wobig, J.L. Congenital anomalies of the lacrimal system. In: ?Surgery of the eyelids and the lacrimal system?. Birmingham, Aesculapius, 1976. p. 157?173.
4. Larsson, S. & Lindgren, S. Surgical treatment of congenital atresia of the nasolacrimal duct. Acta Ophthal. 35: 411?415 (1957).
5. Picó, G. Congenital anomalies of the lacrimal system. In: E.R. Veirs, ?The lacrimal system?. Saint Louis, Mosby, 1971. p. 3?9.