@book{30223,
	author = {Date, C. J.},
	title = {SQL and relational theory},
	publisher = {O'Reilly Media,},
	year = {2012},
	series = {Theory in practice},
	address = {Sebastopol, CA :},
	edition = {2nd ed.},
	url = {http://www.columbia.edu/cgi-bin/cul/resolve?clio9731663}
}