@inproceedings{SIGMOD-1981-Sagiv,
	author        = "Yehoshua Sagiv",
	booktitle     = "{Proceedings of the 11th ACM SIGMOD International Conference on Management of Data}",
	cdrom         = "SIGMOD81/P108.PDF",
	doi           = "10.1145/582318.582336",
	pages         = "108--120",
	publisher     = "{ACM Press}",
	title         = "{Can We Use the Universal Instance Assumption Without Using Nulls?}",
	year          = 1981,
}