@inproceedings{LICS-1991-Ryan,
	author        = "Mark Ryan",
	booktitle     = "{Proceedings of the Sixth Annual Symposium on Logic in Computer Science}",
	doi           = "10.1109/LICS.1991.151660",
	isbn          = "0-8186-2230-X",
	pages         = "362--373",
	publisher     = "{IEEE Computer Society}",
	title         = "{Defaults and Revision in Structured Theories}",
	year          = 1991,
}