1. Aman, M.G., Sarphare, G., & Burrow, W. H. (1995). Psychotropic drug use in group homes: prevalence and relation to demographic / psychiatric variables. American Journal on Mental Retardation, 99, 500–509.
2. Billstedt, E., Gillberg, C., & Gillberg, C. (2005). Autism after adolescence: population-based 13- to 22-year follow-up study of 120 individuals with autism diagnosed in childhood. Journal of Autism and Developmental Disorders, 35, 351–360.
3. Bouras N. (eds), (1999). Psychiatric and behavioural disorders in developmental disabilities and mental retardation. Cambridge: Cambridge University Press.
4. Carr, E. G., Horner, R., & Turnbull, A. P. (1999). Positive behaviour support in people with developmental disabilities: a research synthesis (Monograph (American Association on Mental Retardation). Washington, DC: American Association on Mental Retardation.
5. Didden, R., Duker, P. C., & Korzilius, H. (1999). Meta-analytic study on treatment effectiveness for problem behaviors with individuals who have mental retardation. American Journal of Mental Retardation, 101, 387–399.