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Grimm D, Tilly K, Byram R, Stewart PE, Krum JG, Bueschel DM, Schwan TG, Policastro PF, Elias AF, Rosa PA.Grimm D, et al. Among authors: policastro pf.Proc Natl Acad Sci U S A. 2004 Mar 2;101(9):3142-7. doi: 10.1073/pnas.0306845101. Epub 2004 Feb 17.Proc Natl Acad Sci U S A. 2004.PMID: 14970347Free PMC article.