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Coen DM, Kosz-Vnenchak M, Jacobson JG, Leib DA, Bogard CL, Schaffer PA, Tyler KL, Knipe DM.Coen DM, et al.Proc Natl Acad Sci U S A. 1989 Jun;86(12):4736-40. doi: 10.1073/pnas.86.12.4736.Proc Natl Acad Sci U S A. 1989.PMID: 2543985Free PMC article.