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Harley MJ, Schildbach JF.Harley MJ, et al. Among authors: schildbach jf.Proc Natl Acad Sci U S A. 2003 Sep 30;100(20):11243-8. doi: 10.1073/pnas.2035001100. Epub 2003 Sep 22.Proc Natl Acad Sci U S A. 2003.PMID: 14504391Free PMC article.