@inproceedings{SIGMOD-2010-TranC,
	author        = "Quoc Trung Tran and Chee-Yong Chan",
	booktitle     = "{Proceedings of the 28th ACM SIGMOD International Conference on Management of Data}",
	doi           = "10.1145/1807167.1807172",
	isbn          = "978-1-4503-0032-2",
	pages         = "15--26",
	publisher     = "{ACM}",
	title         = "{How to ConQueR why-not questions}",
	year          = 2010,
}