1. Achenbach TM (1966) The classification of children’s psychiatric symptoms: a factor analytic study. Psychol Monogr 80(7):615
2. Achenbach TM, Edelbrock CS (1983) Manual for the child behavior checklist and the revised behavior profile. Department of Psychiatry, University of Vermont, Burlington
3. Acredelo C (1982) Conservation/nonconservation: alternative explanations. In: Brainerd CJ (ed) Progress in cognitive development, vol 1. Springer, Berlin Heidelberg New York
4. American Psychiatric Association (1978) Diagnostic and statistical manual of mental disorders, 3rd rev edn. Association, Washington DC
5. American Psychiatric Association (1987) Diagnostic and statistical manual of mental disorders, 3rd rev edn. Association, Washington DC, pp 335, 340–342