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Hill TM, Tecklenburg ML, Pelletier AJ, Kuempel PL.Hill TM, et al. Among authors: pelletier aj.Proc Natl Acad Sci U S A. 1989 Mar;86(5):1593-7. doi: 10.1073/pnas.86.5.1593.Proc Natl Acad Sci U S A. 1989.PMID: 2646639Free PMC article.