1. American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders IV (4th ed.). Washington DC: American Psychiatric Association.
2. American Psychiatric Association. (2000). Diagnostic and statistical manual of mental disorders IV-TR. Washington DC: American Psychiatric Association.
3. Baron-Cohen, S., Scott, F. J., Allison, C., Williams, J., Bolton, P., Matthews, F. E., et al. (2009). Prevalence of autism-spectrum conditions: UK school-based population study. British Journal of Psychiatry, 194, 500–509.
4. Blaxill, M. F. (2004). What’s going on? The question of time trends in autism. Public Health Reports, 119, 536–551.
5. Centers for Disease Control and Prevention. (2009). Autism and developmental disabilities monitoring network surveillance year 2006 principal investigators. Prevalence of autism spectrum disorders—autism and developmental disabilities monitoring network, United States, 2006. Morbidity and Mortality Weekly Report. MMWR. CDC Surveillance Summaries, 58, 1–20.