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Acton RT, Weinheimer PF, Hall SJ, Niedermeier W, Shelton E, Bennett JC.Acton RT, et al. Among authors: niedermeier w.Proc Natl Acad Sci U S A. 1971 Jan;68(1):107-11. doi: 10.1073/pnas.68.1.107.Proc Natl Acad Sci U S A. 1971.PMID: 5276279Free PMC article.