1. Arch;BISWELL, R.;Ophthal. (Chicago),1969
2. Amer;BLUMENTHAL, M.;J. Ophthal,1968
3. Amer;DHANDA, R.P.;Trachome,1963
4. Arch;FORSTER, R.K.; FINE, M.;Ophthal. (Chicago); In "The Cornea: First World Congress,1971
5. Brit;Butterworth, London M.U.E.L.L.E.R.; O., F.; O'NEIL, P.; ROPER, T.R.E.V.O.R.; D, P.;J. Ophthal,1967