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Graham E Quinn; e-ROP Cooperative Group.Graham E Quinn, et al.Ophthalmic Epidemiol. 2014 Aug;21(4):256-67. doi: 10.3109/09286586.2014.926940. Epub 2014 Jun 23.Ophthalmic Epidemiol. 2014.PMID: 24955738Free PMC article.