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Craig HM, Pandori MW, Guatelli JC.Craig HM, et al.Proc Natl Acad Sci U S A. 1998 Sep 15;95(19):11229-34. doi: 10.1073/pnas.95.19.11229.Proc Natl Acad Sci U S A. 1998.PMID: 9736718Free PMC article.