1. Thygeson, P., and Dawson, C. R.: Pseudotrachoma caused by molluscum contagiosum virus and various chemical irritants. In Solanes, M. P. (ed.): Concilium Ophthalmologica. Twenty-first Congress, Mexico City, 1970. Amsterdam, Acta Excerpta Medica, 1971, pp. 1894–1897.
2. Marginal corneal ulcer due to B. streptococcus.;Kim;Arch. Ophthalmol.,1977
3. Marginal corneal infiltrates and ulcers;Thygeson;Trans. Am. Acad. Ophthalmol. Otolaryngol.,1947
4. Marginal ulceration of the cornea;Chignell;Br. J. Ophthalmol.,1970