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Butler B, Pirrotta V, Irminger-Finger I, Nöthiger R.Butler B, et al.EMBO J. 1986 Dec 20;5(13):3607-13. doi: 10.1002/j.1460-2075.1986.tb04689.x.EMBO J. 1986.PMID: 3030733Free PMC article.