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Parsons SF, Mallinson G, Holmes CH, Houlihan JM, Simpson KL, Mawby WJ, Spurr NK, Warne D, Barclay AN, Anstee DJ.Parsons SF, et al. Among authors: simpson kl.Proc Natl Acad Sci U S A. 1995 Jun 6;92(12):5496-500. doi: 10.1073/pnas.92.12.5496.Proc Natl Acad Sci U S A. 1995.PMID: 7777537Free PMC article.