@inproceedings{ICALP-2003-AgeevYZ,
	author        = "Alexander A. Ageev and Yinyu Ye and Jiawei Zhang",
	booktitle     = "{Proceedings of the 30th International Colloquium on Automata, Languages and Programming}",
	doi           = "10.1007/3-540-45061-0_13",
	isbn          = "3-540-40493-7",
	pages         = "145--156",
	publisher     = "{Springer International Publishing}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Improved Combinatorial Approximation Algorithms for the k-Level Facility Location Problem}",
	volume        = 2719,
	year          = 2003,
}