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Key NS, Vercellotti GM, Winkelmann JC, Moldow CF, Goodman JL, Esmon NL, Esmon CT, Jacob HS.Key NS, et al.Proc Natl Acad Sci U S A. 1990 Sep;87(18):7095-9. doi: 10.1073/pnas.87.18.7095.Proc Natl Acad Sci U S A. 1990.PMID: 2169619Free PMC article.