@inproceedings{SIGMOD-2006-ZhangHCWLC,
	author        = "Zhen Zhang and Seung-won Hwang and Kevin Chen-Chuan Chang and Min Wang and Christian A. Lang and Yuan-Chi Chang",
	booktitle     = "{Proceedings of the 24th ACM SIGMOD International Conference on Management of Data}",
	doi           = "10.1145/1142473.1142515",
	isbn          = "1-59593-256-9",
	pages         = "359--370",
	publisher     = "{ACM}",
	title         = "{Boolean + ranking: querying a database by k-constrained optimization}",
	year          = 2006,
}