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Simonsz HJ, Crone RA, van der Meer J, Merckel-Timmer CF, van Mourik-Noordenbos AM.Simonsz HJ, et al.Vision Res. 1985;25(12):1977-82. doi: 10.1016/0042-6989(85)90022-7.Vision Res. 1985.PMID: 3832623