@inproceedings{VLDB-1978-EhrigKW,
	author        = "Hartmut Ehrig and Hans-Jörg Kreowski and Herbert Weber",
	booktitle     = "{Proceedings of the Fourth International Conference on Very Large Data Bases}",
	cdrom         = "VLDB78/P427.PDF",
	pages         = "427--440",
	publisher     = "{IEEE Computer Society}",
	title         = "{Algebraic Specification Schemes for Data Base Systems}",
	year          = 1978,
}