1. Effectiveness of combining tangible symbols with the picture exchange communication system to teach requesting skills to children with multiple disabilities including visual impairment;Ali;Education and Training in Autism and Developmental Disabilities,2011
2. Evidence-based practice in communication disorders [Position Statement];American Speech-Language-Hearing Association,2005
3. Blind children's language: Resolving some differences;Anderson;Journal of Child Language,1984
4. Interaction, conversation, and the development of language;Bates,1977
5. Augmentative and alternative communication: Management of severe communication disorders in children and adults;Beukelman,1998