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Preston SJ, Arnold MH, Buchanan WW.Preston SJ, et al.Aust N Z J Ophthalmol. 1989 May;17(2):111-20. doi: 10.1111/j.1442-9071.1989.tb00498.x.Aust N Z J Ophthalmol. 1989.PMID: 2667578Review.