user- In Proc. of PerSWeb-2005 Workshop: Personalisation on the Semantic Web at User Modelling 2005: 10th International Conference, page 2005. (2005)
- ITiCSE '08: Proceedings of the 13th annual SIGCSE conference on Innovation and technology in computer science education, New York, NY. USA, ACM Press, (2008)
- Springer, (2006)
- (June 2005)
- Little, Brown, (1998)
- Proceedings of Middleware 2004, page 232-253. (2004)
- O'Reilly, (2007)
- http://www.technologyreview.com/web/23100/, (July 2009)Retrieved from the web on 08-03-2009 .
- Proceedings of the Tenth International World Wide Web Conference WWW10, page 285-287. Hong Kong, ACM, (May 2001)
- Creating New Learning Experiences on a Global Scale. Second European Conference on Technology Enhanced Learning, EC-TEL 2007, page 293--305. Crete, Greece, Springer, (2007)
- (2007)
- In Proceedings of the IADIS International Conference e-Learning 2007, Lisbon, Portugal, IADIS, IADIS Press, (July 2007)
- Open Source for Knowledge and Learning Management: Strategies Beyond Tools, Hershey, PA, USA, Idea Group Publishing, (2007)
- ERCIM News. Special: Safety-Critical Software (Oktober 2008)
- Python Magazine 3(2):18-25 (2009)
- Proceedings of SIGIR'09, page 612-619. Boston, Massachusettes, USA, ACM, (July 2009)
- (December 2004)
- Grundlagen der Information und Dokumentation, K. G. Saur, Munich, 5th edition, (2004)
- Handbuch E-Learning, Fachverlag Deutscher Wirtschaftsdienst, Köln, (2002)
- Computers as Cognitive Tools. No More Walls, Volume II, Lawrence Erlbaum Associates, Mahwah, NJ, USA, (2000)
