1. Human Motor Control Section; National Institute of Neurological Disorders and Stroke; National Institutes of Health; Bethesda Maryland USA
2. Department of Medicine; Faculty of Medicine; King Chulalongkorn Memorial Hospital; Chulalongkorn Unibersity; Bankok Tailand
3. Department of Medicine; Faculty of Medicine; Siriraj Hospital; Mahidol University; Bankok Thailand