1. Some physiological aspects of the precorneal tear film;Mishima;Arch. Ophth.,1965
2. Anatomy of the Human Orbit and Accessory Organs of Vision;Whitnall,1932
3. Whitnall, S.E.: Ibid, p. 214.
4. Czermak, W.: Die Topographischen Beziehungen der Augnehohle etc. Augenarzliche Unterrichtstafeln (Magnus) 1895 IX Breslau.
5. Control of tearing by blocking the nasal ganglion;Ruskin;Arch. Ophth.,1917