@inproceedings{pig07a,
author = "G. Pigozzi and S. Hartmann",
title  = "Aggregation in Multi-Agent Systems and the Problem of Truth-Tracking",
booktitle = "Proceedings of The Sixth International Joint Conference on
             Autonomous Agents and Multiagent Systems (AAMAS 07)"
location = "Honolulu, Hawai'i, USA",
pages = "674--676,
year = "2007"}