1. 1st Neurology Department, Aeginition Hospital, Medical School, National & Kapodistrian University of Athens, Athens, Greece
2. Merz Pharmaceuticals GmbH, Frankfurt am Main, Germany
3. Department of Neurology, Georgetown University Hospital Pasquerilla Healthcare Center, Washington, DC, USA
4. Parkinson’s Disease Center and Movement Disorders Clinic, Department of Neurology, Baylor College of Medicine, Houston, TX, USA