@inproceedings{STOC-1988-FederG,
	author        = "Tomás Feder and Daniel H. Greene",
	booktitle     = "{Proceedings of the 20th Annual ACM Symposium on Theory of Computing}",
	doi           = "10.1145/62212.62255",
	isbn          = "0-89791-264-0",
	pages         = "434--444",
	publisher     = "{ACM}",
	title         = "{Optimal Algorithms for Approximate Clustering}",
	year          = 1988,
}