title: SYMBOL COMMUNICATION FOR THE MENTALLY HANDICAPPED.
mesh_terms: D000293:Adolescent; D002547:Cerebral Palsy / Q000534:rehabilitation; D002648:Child; D004495:Education of Persons with Intellectual Disabilities; D005260:Female; D006801:Humans; D008607:Intellectual Disability / Q000534:rehabilitation; D008297:Male; D009633:Nonverbal Communication; D009864:Ontario; D013664:Teaching Materials; D013997:Time Factors