Olfactory Testing Differentiates Between Progressive Supranuclear Palsy & Idiopathic Parkinson's Dis
Neurol 43:962-965, Doty,R.L.,et al, 1993
The Olfactory and Cognitive Deficits of Parkinson's Disease:Evidence for Independence
Ann Neurol 25:166-171, Doty,R.L.,et al, 1989