Y. Chan, and D. Roth. Proceedings of the 49th Annual Meeting of the Association for Computational Linguistics: Human Language Technologies - Volume 1, page 551--560. Stroudsburg, PA, USA, Association for Computational Linguistics, (2011)
J. Illig, A. Hotho, R. Jäschke, and G. Stumme. Knowledge Processing and Data Analysis, volume 6581 of Lecture Notes in Computer Science, Springer Berlin / Heidelberg, 10.1007/978-3-642-22140-8_9.(2011)