@inproceedings{SIGIR-1981-Bookstein,
	author        = "Abraham Bookstein",
	booktitle     = "{Proceedings of the Fourth International Conference on Information Storage and Retrieval}",
	cdrom         = "SIGIR1981/P004.pdf",
	doi           = "10.1145/511754.511756",
	isbn          = "0-89791-052-4",
	pages         = "4--14",
	publisher     = "{ACM}",
	title         = "{The Generalized Retrieval Problem}",
	year          = 1981,
}