1. BALAKRISHNAN, E. (1961). Brit. J. Ophthal., 45, 150.
2. CHANDY, J., and VAISHNAVA, S. (1958). Ind. J. Child Hith, 7, 441.
3. DAvE, C. J. (1950). Ind. med. Gaz., 85, 92.
4. DIxoN, H. B. F., and HARGREAVES, W. H. (1944). Quart J. Med., n.s. 13, 107.
5. DOGRA, J. R., and AHERN, D. M. (1935). Ind. med. Gaz., 70, 510.