1. Keltner JL, May WN, Johnson CA, Post RB. The California syndrome. Ophthalmology 1985;92:427. 435.
2. McBride ME. Disability Evaluation and Principles of Treatment of Compensable Injuries 1968;6th ed. 465-479.
3. AMA's Guides to the Evaluation of Permanent Impairment 2001;5th ed. 1st ed, 1971.