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Walder RY, Walder JA.Walder RY, et al. Among authors: walder ja.Proc Natl Acad Sci U S A. 1988 Jul;85(14):5011-5. doi: 10.1073/pnas.85.14.5011.Proc Natl Acad Sci U S A. 1988.PMID: 2839827Free PMC article.