1. Parkinson’s disease;Marsden;J Neurol Neurosurg Psychiatry,1994
2. Therapeutic strategies in Parkinson’s disease;Jankovic,1998
3. Levodopa: long-term impact on Parkinson’s disease;Anonymous;Br Med J,1981
4. Levodopa therapy in Parkinson’s disease;Koller;Neurology,1990
5. “On-off" phenomenon with levodopa therapy in parkinsonism;Fahn;Neurology,1980