Y. Yanbe, A. Jatowt, S. Nakamura, and K. Tanaka. JCDL '07: Proceedings of the 7th ACM/IEEE-CS Joint Conference on Digital Libraries, page 107--116. New York, NY, USA, ACM, (2007)
A. Brew, D. Greene, and P. Cunningham. Proceedings of the 19th European Conference on Artificial Intelligence, volume 215 of Frontiers in Artificial Intelligence and Applications, page 145--150. Amsterdam, The Netherlands, The Netherlands, IOS Press, (2010)
A. Zehe, M. Becker, F. Jannidis, and A. Hotho. KI 2017: Advances in Artificial Intelligence, page 387--394. Cham, Springer International Publishing, (2017)