@inproceedings{SIGMOD-2004-PolyzotisGI,
	author        = "Neoklis Polyzotis and Minos N. Garofalakis and Yannis E. Ioannidis",
	booktitle     = "{Proceedings of the 32nd ACM SIGMOD International Conference on Management of Data}",
	doi           = "10.1145/1007568.1007599",
	isbn          = "1-58113-859-8",
	pages         = "263--274",
	publisher     = "{ACM}",
	title         = "{Approximate XML Query Answers}",
	year          = 2004,
}