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Lenferink AE, Simpson JF, Shawver LK, Coffey RJ, Forbes JT, Arteaga CL.Lenferink AE, et al. Among authors: simpson jf.Proc Natl Acad Sci U S A. 2000 Aug 15;97(17):9609-14. doi: 10.1073/pnas.160564197.Proc Natl Acad Sci U S A. 2000.PMID: 10931950Free PMC article.