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Colbert RA, Rowland-Jones SL, McMichael AJ, Frelinger JA.Colbert RA, et al.Proc Natl Acad Sci U S A. 1993 Jul 15;90(14):6879-83. doi: 10.1073/pnas.90.14.6879.Proc Natl Acad Sci U S A. 1993.PMID: 7688130Free PMC article.