@inproceedings{SIGIR-2006-LiuC,
	author        = "Xiaoyong Liu and W. Bruce Croft",
	booktitle     = "{Proceedings of the 29th International ACM SIGIR Conference on Research and Development in Information Retrieval}",
	doi           = "10.1145/1148170.1148310",
	isbn          = "1-59593-369-7",
	pages         = "671--672",
	publisher     = "{ACM}",
	title         = "{Representing clusters for retrieval}",
	year          = 2006,
}