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Stein JD, Vanderbeek BL, Talwar N, Nan B, Musch DC, Zacks DN.Stein JD, et al.Invest Ophthalmol Vis Sci. 2011 Aug 29;52(9):6842-8. doi: 10.1167/iovs.11-7179.Invest Ophthalmol Vis Sci. 2011.PMID: 21778274Free PMC article.