1. Anderson, C. 1992, March. The boy who wouldn't talk.Guideposts, pp. 11–13.
2. Beck, A.T., and A. Beamesderfer. 1974. Assessment of depression: The depression inventory. In Modern problems in pharmacopsychiatry, ed P. Pichot, pp. 15–169. Basel, Switzerland: Karger.
3. Beck, A.T., and R.A. Steer. 1987.Beck Depression Inventory (BDI) Manual.San Antonio: Psychological Corporation.
4. Internal consistencies of the original and revised beck depression inventory