Degenerative Diseases of the Nervous System, Parkinson DiseaseAdams & Victors Principles of Neurology, Chp 39, pg 1082, Ropper, A.H.,et al, 2014
Ocular Myasthenia:A Protean DisorderSurvey of Ophthalmology 39:169-210, Weinberg,D.A.,et al, 1994