1. Anderson, J. R. (1989). Practice, working memory, and the ACT theory of skill acquisition: A comment on Carlson, Sullivan, and Schneider. Journal of Experimental Psychology: Learning, Memory, and Cognition, 15, 527–530.
2. BBC. (2012a). The Archers.
http://www.bbc.co.uk/radio4/features/the-archers/
3. BBC. (2012b). The Flatmates.
http://www.bbc.co.uk/worldservice/learningenglish/flatmates
4. LNCS 6872;H-J Chen,2011
5. Derrington, M. de J. (2011). Setting up a virtual world for teaching language: Why OpenSim? In Proceedings from the RELIVE11 conference (pp. 43–52). Milton Keynes: Open University.