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Greenwood RD, Nadas AS, Rosenthal A, Freed MD, Bernhard WF, Castaneda AR.Greenwood RD, et al. Among authors: freed md.Am Heart J. 1977 Jul;94(1):14-20. doi: 10.1016/s0002-8703(77)80338-4.Am Heart J. 1977.PMID: 68671