T. Gossen, M. Kotzyba, and A. Nürnberger. Advances in Information Retrieval, volume 9022 of Lecture Notes in Computer Science, page 781-784. Springer International Publishing, (2015)
T. Gossen, M. Nitsche, and A. Nürnberger. Advances in Information Retrieval, 36th European Conference on IR Research, ECIR 2014, volume 8416 of Lecture Notes in Computer Science, page 746-749. Springer International Publishing, (2014)