Friedreich Ataxia
In Rowland, L. P. Merritt's Textbook of Neurology, 8th Ed, Lea & Febiger, Phila, Ch 13, p627, Rosenberg,R.N., 1989
Skeletel Fluorosis
In Vinken PJ, Bruyn GE, Ed, Handbook of Clin Neurol, Vol 36, North-Holland Publ Co, 465, Reddy,D.R., 1979