1. The Late Talker: What To Do If Your Child Isn't Talking Yet;Agin,2003
2. Beyond Baby Talk: From Sounds to Sentences. A Parent's Complete Guide to Language Development;Apel,2001
3. Bilingualism in Development: Language, Literacy and Cognition;Bialystock,2001
4. The child with delayed speech;Richardson;Contemp Pediatr,1992
5. Language and communication in early childhood;Thal;Pediatr Ann,1989