@inproceedings{PODS-2007-GreenKT,
	author        = "Todd J. Green and Gregory Karvounarakis and Val Tannen",
	booktitle     = "{Proceedings of the 26th Symposium on Principles of Database Systems}",
	doi           = "10.1145/1265530.1265535",
	isbn          = "978-1-59593-685-1",
	pages         = "31--40",
	publisher     = "{ACM}",
	title         = "{Provenance semirings}",
	year          = 2007,
}