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2. FRANCESCHETI, A., JACCOTTET, M., and JADASSOHN, W. (1957). Ophthalmologica (Basel), 133, 259.
3. ROSSANO, R., JADASSOHN, W., and PAILLAiD, R. (1956). Dermatologica (Basel), 112, 512.
4. HOLTHUIS, P. (1943). Ophthalmologica (Basel), 106, 325. JoNKERS, G. H. (1950). Ibid., 120, 365.
5. LEFFERTSTRA, L. J. (1956). Ibid., 132, 204.