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Blake MJ, Udelsman R, Feulner GJ, Norton DD, Holbrook NJ.Blake MJ, et al.Proc Natl Acad Sci U S A. 1991 Nov 1;88(21):9873-7. doi: 10.1073/pnas.88.21.9873.Proc Natl Acad Sci U S A. 1991.PMID: 1658790Free PMC article.