1. Challenging behaviour survey;Alborz,1994
2. Prevalence of destructive behaviors;Borthwick-Duffy,1994
3. The HARC Challenging Behaviour Project. Report 5;Emerson,1997
4. The HARC Challenging Behaviour Project. Report 2;Emerson,1997
5. The form and function of challenging behaviours;Emerson;Journal of Intellectual Disability Research,1995