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Dracopoli NC, Harnett P, Bale SJ, Stanger BZ, Tucker MA, Housman DE, Kefford RF.Dracopoli NC, et al. Among authors: bale sj.Proc Natl Acad Sci U S A. 1989 Jun;86(12):4614-8. doi: 10.1073/pnas.86.12.4614.Proc Natl Acad Sci U S A. 1989.PMID: 2734311Free PMC article.