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\newblock {\em Rules of Play}.
\newblock The MIT Press, 2004.

\bibitem{bartle}
Richard Bartle.
\newblock Hearts, clubs, diamonds, spades: Players who suit {MUDs}.
\newblock http://aigamedev.com/open/interviews/mario-ai/, 1996.
\newblock [Online; accessed 18-March-2012].

\bibitem{forgy}
C.~Forgy.
\newblock Rete: A fast algorithm for the many pattern/many object pattern match
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\newblock {\em Artificial Intelligence}, 19:17--37, 1982.

\end{thebibliography}
