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O'Sullivan SS, Johnson M, Williams DR, Revesz T, Holton JL, Lees AJ, Perry EK.O'Sullivan SS, et al.Mov Disord. 2011 Jan;26(1):45-50. doi: 10.1002/mds.23340. Epub 2010 Nov 16.Mov Disord. 2011.PMID: 21322018