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Ringvold A, Nicolaissen B Jr.Ringvold A, et al. Among authors: nicolaissen b jr.Acta Ophthalmol (Copenh). 1990 Jun;68(3):310-6. doi: 10.1111/j.1755-3768.1990.tb01928.x.Acta Ophthalmol (Copenh). 1990.PMID: 2392908