Falscher Engel: Mein Höllentrip als Undercover-Agent bei den Hells Angels. Ullstein Taschenbuch, 2011. [PUMA: agent angels engel falscher hells höllentrip undercover]
A Taxonomy of Recommender Agents on the Internet. Artificial Intelligence Review, (19)4:285--330, Kluwer Academic Publishers, 2003. [PUMA: agent recommender survey] URL
Searching social networks. Proceedings of the second international joint conference on Autonomous agents and multiagent systems, 65--72, ACM, New York, NY, USA, 2003. [PUMA: agent collaborative network search social web] URL
The Origins of Ontologies and Communication Conventions in Multi-Agent Systems. Autonomous Agents and Multi-Agent Systems, (1)2:169-194, Oktober 1998. [PUMA: agent ontologies sosbuch] URL
An Adaptive Agent for Web Exploration Based of Concept Hierarchies. Proceedings of the 9th International Conference on Human Computer Interaction, New Orleans, LA, 2001. [PUMA: exploration web agent adaptive concept hierarchies based] URL