@inproceedings{ECOOP-1991-Wills,
	author        = "Alan Wills",
	booktitle     = "{Proceedings of the Fifth European Conference on Object-Oriented Programming}",
	doi           = "10.1007/BFb0057015",
	editor        = "Pierre America",
	isbn          = "3-540-54262-0",
	pages         = "59--76",
	publisher     = "{Springer-Verlag}",
	series        = "{Lecture Notes in Computer Science}",
	title         = "{Capsules and Types in Fresco: Program Verification in Smalltalk}",
	volume        = 512,
	year          = 1991,
}