1. Amer;BEN-SIRA, I.; TICHO, U.;J. Ophthal,1969
2. BERSON, D., ZAUBERMAN, H., LANDAU, L., and BLUMENTHAL, M. (1969)
3. Trans;CAIRNS, J.E.;Ibid,1968
4. LINNER, E. (1969) Trans. ophthal. Soc. U.K., 89, 475
5. Personal communication;QUARCOOPOME, C. 0,1970