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Blumenthal JA, Barefoot J, Burg MM, Williams RB Jr.Blumenthal JA, et al.Br J Med Psychol. 1987 Dec;60 ( Pt 4):349-55. doi: 10.1111/j.2044-8341.1987.tb02754.x.Br J Med Psychol. 1987.PMID: 3426973