American Psychiatric Association : Diagnostic and Statistical Manual of Mental Disorders, 4th ed. (DSM-IV). APA, Washington, D.C., 1994.
Ehlers, S. and Gillberg, C.: The epidemiology of Asperger syndrome ; a total population study. J. Child Psychol. Psychiatry, 34 ; 1327-1350, 1993.
Honda, H., Shimizu, Y., Misumi, K. et al. : Cumulative incidence and prevalence of childhood autism in children in Japan. Br. J. Psychiatry, 169 ; 228-235, 1996.