Thomas Bocek, Wang Kun, Fabio Victora Hecht, David Hausheer, Burkhard Stiller: PSH: A Private and Shared History-based Incentive Mechanism; in: EMANICS Workshop on Economic Traffic Management , Zurich, Switzerland, August 2008, pp 1-25. URL: http://www.csg.uzh.ch/staff/bocek/publications/etm08_psh.pdf.