J. Arrasvuori, and J. Holm. DIMEA '07: Proceedings of the 2nd international conference on Digital interactive media in entertainment and arts, page 20--27. New York, NY, USA, ACM, (2007)
C. Basu, H. Hirsh, and W. Cohen. AAAI '98/IAAI '98: Proceedings of the fifteenth national/tenth conference on Artificial intelligence/Innovative applications of artificial intelligence, page 714-720. Menlo Park, CA, USA, American Association for Artificial Intelligence, (1998)