@inproceedings{STOC-1972-ConstableM,
	author        = "Robert L. Constable and Steven S. Muchnick",
	booktitle     = "{Proceedings of the Fourth Annual ACM Symposium on Theory of Computing}",
	doi           = "10.1145/800152.804892",
	pages         = "1--17",
	publisher     = "{ACM}",
	title         = "{Subrecursive Program Schemata I & II: I. Undecidable Equivalence Problems; II. Decidable Equivalence Problems}",
	year          = 1972,
}