D. Maynard, Y. Li, and W. Peters. Proceedings of the 2008 conference on Ontology Learning and Population: Bridging the Gap between Text and Knowledge, page 107-127. IOS Press, (2008)
R. Witte, N. Khamis, and J. Rilling. The Seventh International Conference on Language Resources and Evaluation (LREC 2010), page 3845--3850. Valletta, Malta, ELRA, (May 2010)