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Voss SD, Leary TP, Sondel PM, Robb RJ.Voss SD, et al.Proc Natl Acad Sci U S A. 1993 Mar 15;90(6):2428-32. doi: 10.1073/pnas.90.6.2428.Proc Natl Acad Sci U S A. 1993.PMID: 7681595Free PMC article.