1. American Psychiatric Association. (1980). Diagnostic and statistical manual of mental disorders (3rd ed.).Washington, DC: Author.
2. American Psychiatric Association. (1987). Diagnostic and statistical manual of mental disorders (3rd ed., rev.).Washington, DC: Author.
3. American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (4th ed.).Washington, DC: Author.
4. Beck, A. T. & Steer, R. A. (1993a).Manual for the Beck Anxiety Inventory. San Antonio, TX: Psychological Corporation.