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Grady CL, McIntosh AR, Rajah MN, Craik FI.Grady CL, et al.Proc Natl Acad Sci U S A. 1998 Mar 3;95(5):2703-8. doi: 10.1073/pnas.95.5.2703.Proc Natl Acad Sci U S A. 1998.PMID: 9482951Free PMC article.