5Baker, C. and Jones, S. P. Encyclopedia of Bilingualism and Bilingual Education. Multilingual Matters Ltd, 1998.
6Darcy, N. T. A review of the literature on the effects of bilingualism upon the measurement of intelligence. The Journal of Genetic Psychology, 1953, 82, 21-57.
7Lindholm, K. J. Bilingual children: some interpretations of cognitive and linguistic development. In K. E. Nelson (ed.),Children's Language, Vol. 2, Gardner Press, Inc., 1980.
8Leopold, W. F. Speech Development of a Bilingual Children - A Linguist's Record, Vol. 1-4. Northwestern University Press, 1932-1949.
9Peal, E. and Lambert, W. E. The relation of bilingualism to intelligence. Psychological Monographs: General and Applied, 1962, 76(27), 1-23.
10Hamers, J. F. and Blanc, H. A. Bilinguality and Bilingualism.Cambridge University Press, 2000.