1. BERNKOPF, H., NISHMI, M., MAYTHAR, B., and FEITELBERG, I. (1959) A.M.A. Arch. Ophthal., 62,33
2. Brit;DUKE-ELDER, S.; JONES, B.R.;J. Ophthal; Medical Microbiology,1958
3. GEAR, J. H. S., CUTHBERTSON, E., and RYAN, J. (1967) Ibid., 63, 1310
4. GORDON, F. B., HARPER, I. A., QUAN, A. L., TREHARNE, J. D., DWYER, R. ST. C., and GARLAND, J. A. (1969)
5. , JAWETZ, E., THYGESON, P., and DAWSON, C. R. (1960) Proc. Soc. exp. Biol. (N.r.), 104, 142