1. Bishop, DM Leonard, B (2000) Speech and language impairments in children: causes, characteristics, intervention and outcome. Journal of Child Language 29(3): 701-711.
2. Bender WA (1998) Learning disabilities: Characteristics, identification, and teaching strategies. Needham Heights Allyn and Bacon, USA.
3. http://apps.who.int/iris/bitstream/10665/177094/1/9789241564960_eng.pdf
4. Epidemiology of speech and language impairment in a nationally representative sample of 4-to 5-year-old children;McLeod;J Speech Lang Hear Res 52(5),2009
5. Screening for speech and language delay in preschool children: Recommendation statement;Preventive Services Task Force;Pediatrics 117(2),2006