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Weston JA, Hendricks KL.Weston JA, et al. Among authors: hendricks kl.Proc Natl Acad Sci U S A. 1972 Dec;69(12):3727-31. doi: 10.1073/pnas.69.12.3727.Proc Natl Acad Sci U S A. 1972.PMID: 4509335Free PMC article.