@inproceedings{SIGIR-1983-Sopena,
	author        = "Luis De Sopena",
	booktitle     = "{Proceedings of the Sixth Annual International ACM SIGIR Conference on Research and Development in Information Retrieval}",
	cdrom         = "SIGIR1983/P075.pdf",
	doi           = "10.1145/511793.511803",
	isbn          = "0-89791-107-5",
	pages         = "75--80",
	publisher     = "{ACM}",
	title         = "{Natural Language Grammars for an Information System}",
	year          = 1983,
}