A. Signorini, und T. Imielinski. Proceedings of the 2009 IEEE International Conference on Semantic Computing, Seite 184--191. Washington, DC, USA, IEEE Computer Society, (2009)
D. Tran, S. Bloehdorn, P. Cimiano, und P. Haase. Proceedings of the 1st International Conference on the Theory of Information Retrieval (ICTIR'07), 18th - 20th October 2007, Budapest, Hungary, Seite 55-68. (2007)