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Siegel WC, Mark DB, Hlatky MA, Harrell FE Jr, Pryor DB, Barefoot JC, Williams RB Jr.Siegel WC, et al. Among authors: williams rb jr.Am J Cardiol. 1989 Dec 1;64(19):1280-3. doi: 10.1016/0002-9149(89)90568-7.Am J Cardiol. 1989.PMID: 2589193
Mark DB, Lam LC, Lee KL, Jones RH, Pryor DB, Stack RS, Williams RB, Clapp-Channing NE, Califf RM, Hlatky MA.Mark DB, et al. Among authors: williams rb.Ann Intern Med. 1994 Jan 15;120(2):111-7. doi: 10.7326/0003-4819-120-2-199401150-00003.Ann Intern Med. 1994.PMID: 8256969Clinical Trial.