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Heaton LA, Hillman BI, Hunter BG, Zuidema D, Jackson AO.Heaton LA, et al. Among authors: hillman bi.Proc Natl Acad Sci U S A. 1989 Nov;86(22):8665-8. doi: 10.1073/pnas.86.22.8665.Proc Natl Acad Sci U S A. 1989.PMID: 2813418Free PMC article.