@inproceedings{SIGMOD-1991-Sheng,
	author        = "Yeh-Heng Sheng",
	booktitle     = "{Proceedings of the 21st ACM SIGMOD International Conference on Management of Data}",
	cdrom         = "SIGMOD91/P188.PDF",
	doi           = "10.1145/115790.115817",
	pages         = "188--197",
	title         = "{A Non-deterministic Deductive Database Language}",
	year          = 1991,
}