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Henein MY, O'Sullivan CA, Ramzy IS, Sigwart U, Gibson DG.Henein MY, et al.J Am Coll Cardiol. 1999 Oct;34(4):1117-22. doi: 10.1016/s0735-1097(99)00332-0.J Am Coll Cardiol. 1999.PMID: 10520800Free article.