@book{120447,
	author = {Coxford, Arthur F., },
	title = {The Ideas of algebra, K-12 : 1988 yearbook /},
	publisher = {National Council of Teachers of Mathematics, },
	year = {1989.},
	series = {Year-book/national council of teachers of mathematics, issn-0077-4103; 1988},
	address = {Reston, virginia :},
	edition = {2a ed.}
}