1. Odlin, T. (1989). Language transfer (Vol. 27). Cambridge: Cambridge University Press.
2. Cenoz, J., Hufeisen, B., & Jessner, U. (2001). Towards trilingual education. International Journal of Bilingual Education and Bilingualism, 4(1), 1-10.
3. Griessler, M. (2001). The effects of third language learning on second language proficiency: An Austrian example. International Journal of Bilingual Education and Bilingualism, 4(1), 50-60.
4. Cabrelli Amaro, J. (2013). The Phonological Permeability Hypothesis: Measuring regressive L3 influence to test L1 and L2 phonological representations (Unpublished doctoral dissertation). University of Florida.
5. Hui, B. (2010). Backward transfer from L3 French to L2 English production of relative clauses by L1 Cantonese speakers in Hong Kong. Hong Kong Journal of Applied Linguistics, 12(2), 45-60.