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2. Avedian, L., & Ruberg, R.L. (1980). Impaired weight gain in cleft palate infants. Cleft Palate Journal , 17 , 4-26.
3. Beers, M., & Baker, A.E. (1998). De fonologische ontwikkeling van dove kinderen in de leeftijd van 4 tot 10 jaar . Amsterdam: Universiteit van Amsterdam, Instituut voor Algemene Taalwetenschap.
4. Bishop, D. (1994). Language development in children with abnormal structure or function of the speech apparatus. Chapter 14. In D. Bishop & K. Mogford (eds). Language development in exceptional circumstances. Hove: Lawrence, Erlbaum (p. 220-39).
5. Bishop, D., & Mogford, K. (1994). Language development in exceptional circumstances. Hove: Lawrence, Erlbaum.