Georg Gottlob, Roberto Zicari
Closed World Databases Opened Through Null Values
VLDB, 1988.
@inproceedings{VLDB-1988-GottlobZ,
author = "Georg Gottlob and Roberto Zicari",
booktitle = "{Proceedings of the 14th International Conference on Very Large Data Bases}",
ee = "http://www.vldb.org/conf/1988/P050.PDF",
isbn = "0-934613-75-3",
pages = "50--61",
publisher = "{Morgan Kaufmann}",
title = "{Closed World Databases Opened Through Null Values}",
year = 1988,
}