1. American Psychiatric Association. (2013). Diagnostic and statistical manual of mental disorders (5th ed.). American Psychiatric Publishing.
2. Andrewes, H. E., Walker, V., & O’Neill, B. (2014). Exploring the use of positive psychology interventions in brain injury survivors with challenging behaviour. Brain Injury, 28(7), 965–971.
3. Asgharipoor, N., Farid, A. A., Arshadi, H., & Sahebi, A. (2012). A Comparative study on the effectiveness of positive psychotherapy and group cognitive behavioural therapy for the patients suffering from major depressive disorder. Iranian Journal of Psychiatry and Behavioral Sciences, 6(2), 33–41.
4. Barlow, D., & Hersen, M. (1984). Single case experimental designs: Strategies for studying behaviour for change. Pergamon Press.
5. Beck, A. T., Rush, A. J., Shaw, B. F., & Emery, G. (1979). Cognitive therapy for depression. Guilford Press.