J. Volz, C. Bizer, M. Gaedke, and G. Kobilarov. The Semantic Web -- ISWC 2009: 8th International Semantic Web Conference, Chantilly, VA, USA, volume 5823 of Lecture Notes in Computer Science, Springer, Berlin, (2009)
C. Costa, G. Beham, W. Reinhardt, and M. Sillaots. Proceedings of the 2nd SIRTEL'08 Workshop on Social Information Retrieval for Technology Enhanced Learning, 382, Maastricht, The Netherlands, (September 2008)