Adesope, O., Lavin, T., Thompson, T., & Ungerleider, C. (2010). A Systematic Review and MetaAnalysis of the Cognitive Correlates of Bilingualism. Review of Educational Research, 80(2), 207 - 245
August, D., & Shanahan, T. (2006) Developing literacy in second-language learners: Report of the National Literacy Panel on language-minority children and youth, Mahwah, NJ: Erlbaum
Baker, C (2011) Foundations of Bilingual Education and Bilingualism, Clevedon: Multilingual Matters Birmingham