- Dr Asha Das, Department of Neurology, National Neuroscience Institute, 11 Jalan Tan Tock Seng, Singapore 308443 email
- Received 29 June 1999
- Revised 4 October 1999
- Accepted 5 October 1999
- Published online 1 March 2000.
If you wish to reuse any or all of this article please use the link below which will take you to the Copyright Clearance Center’s RightsLink service. You will be able to get a quick price and instant permission to reuse the content in many different ways.