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Whiteley PJ, Jensen PE, Pierce CW, Abruzzini AF, Kapp JA.Whiteley PJ, et al.Proc Natl Acad Sci U S A. 1988 Apr;85(8):2723-7. doi: 10.1073/pnas.85.8.2723.Proc Natl Acad Sci U S A. 1988.PMID: 2965814Free PMC article.