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Higgins SJ, Rousseau GG, Baxter JD, Tomkins GM.Higgins SJ, et al. Among authors: baxter jd.Proc Natl Acad Sci U S A. 1973 Dec;70(12):3415-8. doi: 10.1073/pnas.70.12.3415.Proc Natl Acad Sci U S A. 1973.PMID: 4357870Free PMC article.