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Orlando RA, Farquhar MG.Orlando RA, et al. Among authors: farquhar mg.Proc Natl Acad Sci U S A. 1993 May 1;90(9):4082-6. doi: 10.1073/pnas.90.9.4082.Proc Natl Acad Sci U S A. 1993.PMID: 8483924Free PMC article.