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Walsh CM, Blackwell T, Tranah GJ, Stone KL, Ancoli-Israel S, Redline S, Paudel M, Kramer JH, Yaffe K.Walsh CM, et al.Sleep. 2014 Dec 1;37(12):2009-16. doi: 10.5665/sleep.4260.Sleep. 2014.PMID: 25337947Free PMC article.