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Iranzo A, Ratti PL, Casanova-Molla J, Serradell M, Vilaseca I, Santamaria J.Iranzo A, et al.Sleep. 2009 Sep;32(9):1149-53. doi: 10.1093/sleep/32.9.1149.Sleep. 2009.PMID: 19750919Free PMC article.