@inproceedings{POPL-1980-GuttagH,
	author        = "John V. Guttag and James J. Horning",
	booktitle     = "{Conference Record of the Seventh Annual Symposium on Principles of Programming Languages}",
	doi           = "10.1145/567446.567471",
	editor        = "Paul W. Abrahams and Richard J. Lipton and Stephen R. Bourne",
	isbn          = "0-89791-011-7",
	pages         = "251--261",
	publisher     = "{ACM Press}",
	title         = "{Formal Specification as a Design Tool}",
	year          = 1980,
}