Dawson, G., Osterling, J. (1997). Effectiveness and common elements of current approaches. In M. J. Guralnik (Ed.), The Effectiveness of Early Intervention: Second Generation Research. Baltimore, MD: Paul H. Brookes.
Frost, L. a. B., A. (1994). PECS: The Picture Exchange Communication System Training Manual. Cherry Hill, NJ: Pyramid Educational Consultants.
National Research Council (Ed.). (2001). Educating Children with Autism. Washington, D.C.: National Academy Press.
Sundberg, M. L., Partington, J.W. (1998). Teaching Language to Children with Autism or Other Developmental Disabilities. Pleasant Hill, CA: Behavior Analysts, Inc.