@inproceedings{PLILP-1993-ClarkH,
	author        = "David Clark and Chris Hankin",
	booktitle     = "{Proceedings of the Fifth International Symposium on Programming Language Implementation and Logic Programming}",
	doi           = "10.1007/3-540-57186-8_88",
	isbn          = "3-540-57186-8",
	pages         = "318--331",
	publisher     = "{Springer-Verlag}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{A Lattice of Abstract Graphs}",
	volume        = 714,
	year          = 1993,
}