American Association on Mental Retardation. (1992). Mental Retardation: Definition, classification, and systems of supports (9th ed.). Washington, DC: Author.
2.
American Psychiatric Association. (1994). Diagnostic and statistical manual of mental disorders (4th ed.). Washington, DC: Author.
3.
Boan, C. H., & Harrison, P. L. (1997). Adaptive behavior assessment and individuals with mental retardation. In R. L. Taylor (Ed.), Assessment of individuals with mental retardation (pp. 33-53). San Diego, CA: Singular Publishing Group.
4.
Grossman, H. J. (Ed.). (1983). Classification in mental retardation. Washington, DC: American Association on Mental Deficiency.
5.
Heber, R. (1959). Modifications in the manual on terminology and classification in mental retardation (monograph suppl.). American Journal of Mental Deficiency, 64(2), 499-500.
6.
Sparrow, S. S., Balla, D. A., & Cicchetto, D. V. (1985). Vineland Adaptive Behavior Scales-Classroom edition manual. Circle Pines, MN: American Guidance Service.