P. Pietzuch, D. Eyers, S. Kounev, and B. Shand. Proceedings of the 2007 Inaugural International Conference on Distributed Event-Based Systems (DEBS 2007), Toronto, Canada, June 20-22, 2007, volume 233 of ACM International Conference Proceeding Series, page 152--157. ACM, New York, NY, USA, (June 2007)