P. Ludford, D. Cosley, D. Frankowski, and L. Terveen. CHI '04: Proceedings of the SIGCHI conference on Human factors in computing systems, page 631--638. New York, NY, USA, ACM Press, (2004)
W. Adamczak, H. Begemann, and S. Stefani. Presentation at CRIS 2000, (2000)CRIS 2000 - Current Research Information Systems for Europe Conference, Helsinki, Finnland, 2000.