D. Cox, V. Kindratenko, und D. Pointer. UbiComp 2003: Ubiquitous Computing, Volume 2864 von Lecture Notes in Computer Science, Springer, Berlin / Heidelberg, (2003)
J. Scripps, P. Tan, und A. Esfahanian. Proceedings of the 9th WebKDD and 1st SNA-KDD 2007 workshop on Web mining and social network analysis, Seite 26--35. New York, NY, USA, ACM, (2007)