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Beranek DT, White GL, Heflich RH, Beland FA.Beranek DT, et al.Proc Natl Acad Sci U S A. 1982 Sep;79(17):5175-8. doi: 10.1073/pnas.79.17.5175.Proc Natl Acad Sci U S A. 1982.PMID: 6752940Free PMC article.