J. Lehmann, B. Gonçalves, J. Ramasco, und C. Cattuto. Proceedings of the 21st International Conference on World Wide Web, Seite 251--260. New York, NY, USA, ACM, (2012)
T. Sakaki, M. Okazaki, und Y. Matsuo. Proceedings of the 19th international conference on World wide web, Seite 851--860. New York, NY, USA, ACM, (2010)