Jennifer Wortman Yevgeniy Vorobeychik Lihong Li John Langford Maintaining Equilibria During Exploration in Sponsored Search Auctions. 119-130 2007 conf/wine/2007 WINE http://dx.doi.org/10.1007/978-3-540-77105-0_14 db/conf/wine/wine2007.html#WortmanVLL07