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Braun CJ, Siedow JN, Williams ME, Levings CS 3rd.Braun CJ, et al.Proc Natl Acad Sci U S A. 1989 Jun;86(12):4435-9. doi: 10.1073/pnas.86.12.4435.Proc Natl Acad Sci U S A. 1989.PMID: 2660137Free PMC article.