B. Stein, T. Gollub, and D. Hoppe. 20th ACM International Conference on Information and Knowledge Management (CIKM 11), page 2141-2144. ACM, (October 2011)
D. Hoppe. Proceedings of the Schloss Dagstuhl Seminar on Challenges in Document Mining, page 81. Wadern, Germany, Leibniz-Zentrum für Informatik, (April 2011)Invited talk.