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Hess JF, Fox M, Schmid C, Shen CK.Hess JF, et al. Among authors: shen ck.Proc Natl Acad Sci U S A. 1983 Oct;80(19):5970-4. doi: 10.1073/pnas.80.19.5970.Proc Natl Acad Sci U S A. 1983.PMID: 6310609Free PMC article.