@inproceedings{TAV-1989-Howden,
	author        = "William E. Howden",
	booktitle     = "{Proceedings of the Third Symposium on Testing, Analysis, and Verification}",
	doi           = "10.1145/75308.75310",
	pages         = "2--9",
	publisher     = "{ACM}",
	title         = "{Validating Programs without Specifications}",
	year          = 1989,
}