Craig Boutilier David C. Parkes Tuomas Sandholm William E. Walsh Expressive Banner Ad Auctions and Model-Based Online Optimization for Clearing. 30-37 2008 AAAI conf/aaai/2008 db/conf/aaai/aaai2008.html#BoutilierPSW08 http://www.aaai.org/Library/AAAI/2008/aaai08-005.php