1. Epibulbar tumours;Ash, J.E.;American Journal of Ophthalmology,1950
2. Cited by Youngson;Batten, K.L.,1972
3. Pterygium Throughout the World;Cameron, M.E.,1965
4. Conjunctival carcinoma in Northern Sudan;Daoud, E.H.; Osman, A.A.A.;Sudan Medical Journal,1970
5. Aetiology and pathology of pterygium. Transactions of the Ophthalmological Societies of Australia and;Elliot, R.;New Zealand,1966