1. : The Cranial Nerves-Anatomy and Anatomicoclinical Correlation. Oxford, England, Blackwell, 1957, p 57
2. : Core Text of Neuroanatomy. Baltimore, Williams & Wilkins, 1972, pp 74-75, 81-82
3. : The Neurologic Examination. Third edition. New York, Harper & Row, 1970, p 325
4. : Bing's Local Diagnosis in Neurological Diseases. Fifteenth edition. St. Louis, Mosby, 1969, p 181
5. : Disorders of the brain stem and its cranial nerves, in (eds): Clinical Neurology. New York, Harper & Row, 1978, vol 3, pp 2-4