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Hirshkowitz M, Moore CA, O'Connor S, Bellamy M, Cunningham GR.Hirshkowitz M, et al.J Psychosom Res. 1997 Jun;42(6):541-6. doi: 10.1016/s0022-3999(97)00006-8.J Psychosom Res. 1997.PMID: 9226601Clinical Trial.