R. Neßelrath. Proceedings of the 9th International Conference on Intelligent Environments (IE). International Conference on Intelligent Environments (IE-13), July 18-19, Athen, Greece, page 266-269. Washington, DC, USA, IEEE Computer Society, (2013)
P. Brusilovsky, and D. Cooper. Proceedings of the 7th international conference on Intelligent user interfaces, page 23--30. New York, NY, USA, ACM, (2002)