B. Krause, R. Jäschke, A. Hotho, and G. Stumme. HT '08: Proceedings of the nineteenth ACM conference on Hypertext and hypermedia, page 157--166. New York, NY, USA, ACM, (2008)
M. McGlohon, L. Akoglu, and C. Faloutsos. KDD '08: Proceeding of the 14th ACM SIGKDD international conference on Knowledge discovery and data mining, page 524--532. New York, NY, USA, ACM, (2008)