Garrett Wolf Hemal Khatri Bhaumik Chokshi Jianchun Fan Yi Chen Subbarao Kambhampati Query Processing over Incomplete Autonomous Databases. 651-662 2007 conf/vldb/2007 VLDB http://www.vldb.org/conf/2007/papers/research/p651-wolf.pdf db/conf/vldb/vldb2007.html#WolfKCFCK07