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Bittner AK, Ibrahim MA, Haythornthwaite JA, Diener-West M, Dagnelie G.Bittner AK, et al. Among authors: haythornthwaite ja.Optom Vis Sci. 2011 Dec;88(12):1496-506. doi: 10.1097/OPX.0b013e3182348d0b.Optom Vis Sci. 2011.PMID: 21946786Free PMC article.