@inproceedings{conf/scai/Sundin89,
	title = {Asking about Negative Knowledge.},
	author = {Ulf Sundin},
	booktitle = {SCAI},
	pages = {931-942},
	url = {http://dblp.uni-trier.de/db/conf/scai/scai1989.html#Sundin89},
	year = {1989},
	biburl = {http://www.bibsonomy.org/bibtex/26dd10cdf43a694e2fae6e717dacf5b5a/dblp},
	description = {dblp},
	date = {2002-01-03},
	keywords = {dblp }
}