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Ludwig SR, Oppenheimer DG, Silflow CD, Snustad DP.Ludwig SR, et al. Among authors: snustad dp.Proc Natl Acad Sci U S A. 1987 Aug;84(16):5833-7. doi: 10.1073/pnas.84.16.5833.Proc Natl Acad Sci U S A. 1987.PMID: 3475704Free PMC article.