1. Berendt, E. A. (2010).For communication and learning: Research in spoken and applied discourse (3rd ed.). Bangkok: Assumption University Press.
2. Jin, L. & Cortazzi, M. (2008). Images of teachers, learning and questioning in Chinese cultures of learning. In E. A. Berendt (Ed.),Metaphors for learning: Cross-cultural perspectives(pp. 177–202). Amsterdam: John Benjamins.
3. Joos, M. (1962).The five clocks. New York: Harcourt, Brace & World.
4. Lim, L. (Ed.). (2004).Singapore English: A grammatical description. Amsterdam: John Benjamins.
5. Mufwene, S. S. (2001).The ecology of language evolution. Cambridge: Cambridge University Press.