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Carbonetti NH, Simnad VI, Seifert HS, So M, Sparling PF.Carbonetti NH, et al. Among authors: seifert hs.Proc Natl Acad Sci U S A. 1988 Sep;85(18):6841-5. doi: 10.1073/pnas.85.18.6841.Proc Natl Acad Sci U S A. 1988.PMID: 2457919Free PMC article.