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Fredericksen RE, Bex PJ, Verstraten FA.Fredericksen RE, et al. Among authors: bex pj.J Opt Soc Am A Opt Image Sci Vis. 1997 Jan;14(1):1-12. doi: 10.1364/josaa.14.000001.J Opt Soc Am A Opt Image Sci Vis. 1997.PMID: 8988615