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Nelson VR, Heaney JD, Tesar PJ, Davidson NO, Nadeau JH.Nelson VR, et al. Among authors: heaney jd.Proc Natl Acad Sci U S A. 2012 Oct 9;109(41):E2766-73. doi: 10.1073/pnas.1207169109. Epub 2012 Aug 24.Proc Natl Acad Sci U S A. 2012.PMID: 22923694Free PMC article.