RT Journal Article SR Electronic T1 Parkinson disease (January 2012) JF Cleveland Clinic Journal of Medicine JO Cleve Clin J Med FD Cleveland Clinic SP 242 OP 243 DO 10.3949/ccjm.79c:04006 VO 79 IS 4 A1 Keller, David L. YR 2012 UL http://www.ccjm.org/content/79/4/242.3.abstract AB