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Black IW, Hopkins AP, Lee LC, Jacobson BM, Walsh WF.Black IW, et al. Among authors: walsh wf.Br Heart J. 1991 Oct;66(4):302-7. doi: 10.1136/hrt.66.4.302.Br Heart J. 1991.PMID: 1747283Free PMC article.
Black IW, Hopkins AP, Lee LC, Walsh WF.Black IW, et al. Among authors: walsh wf.Am Heart J. 1993 Aug;126(2):375-81. doi: 10.1016/0002-8703(93)91054-i.Am Heart J. 1993.PMID: 8338008