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Yeung WF, Chung KF, Poon MM, Ho FY, Zhang SP, Zhang ZJ, Ziea ET, Wong VT.Yeung WF, et al.Sleep Med Rev. 2012 Dec;16(6):497-507. doi: 10.1016/j.smrv.2011.12.005. Epub 2012 Mar 21.Sleep Med Rev. 2012.PMID: 22440393Review.