1. The dropped head syndrome
2. Engel WK: Rod (nemaline) disease, in Goldensohn ES, Appel SH (eds): Scientific Approaches to Clinical Neurology. Philadelphia , Lea & Febiger, 1977, pp 1668-1669.
3. Riggs JE, Schochet, SS Muscle disease, in Joynt RJ (ed): Clinical Neurology. Philadelphia, JB Lippincott, 1991, chap. 53, p 7.