X. Li, B. Liu, и S. Ng. Proceedings of the 2010 Conference on Empirical Methods in Natural Language Processing, стр. 218--228. Stroudsburg, PA, USA, Association for Computational Linguistics, (2010)
Z. Cao, T. Qin, T. Liu, M. Tsai, и H. Li. Proceedings of the 24th international conference on Machine learning, стр. 129--136. New York, NY, USA, ACM, (2007)