M. Amelung, K. Krieger, and D. Rösner. Lernen im Digitalen Zeitalter - DeLFI 2009: 7. E-Learning Fachtagung Informatik, page 247--258. Bonn, Gesellschaft für Informatik, (2009)ISBN 978-3-88579-247-5 / ISSN 1617-5468.
M. Annett, and E. Stroulia. CASCON '08: Proceedings of the 2008 conference of the center for advanced studies on collaborative research, page 192--206. New York, NY, USA, ACM, (2008)
A. Aschenbrenner, M. Kuster, C. Ludwig, and T. Vitt. Digital Ecosystems and Technologies, 2009. DEST '09. 3rd IEEE International Conference on, page 745 -750. (June 2009)
A. Averbakh, D. Krause, and D. Skoutas. The Semantic Web -- ISWC 2009: 8th International Semantic Web Conference, Chantilly, VA, USA, volume 5823 of Lecture Notes in Computer Science, Springer, Berlin, (2009)
R. Aversa, B. Di artino, and S. Venticinque. Computational Science and Engineering, 2009. CSE '09. International Conference on, 2, page 197-204. (August 2009)