Y. Zheng, F. Liu, und H. Hsieh. International Conference on Knowledge Discovery and Data Mining (SIGKDD), Seite 1436--1444. New York, NY, USA, ACM, (2013)
B. Yu, und M. Singh. Cooperative Information Agents IV - The Future of Information Agents in Cyberspace, Volume 1860 von Lecture Notes in Computer Science, Springer, Berlin/Heidelberg, (2000)