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2. Personal observation-to be published;ASHTON, N.,1960
3. GRAYMORE, C., and PEDLER, C. (1957). Brit. J. Ophthal., 41, 449.
4. "1lth Inst;Saunders, Philadelphia; GRAYMORE, London; C.;Ophthal. Ann. Rep.", p.24. Institute of Ophthalmology, London,1957
5. "1lth Inst;Saunders, Philadelphia; GRAYMORE, London; C.;Ophthal. Ann. Rep.", p.24. Institute of Ophthalmology, London,1957