@book{5431,
	author = {Billstein, Rick. and Billstein, Rick.},
	title = {A problem solving approach to mathematics /},
	publisher = {Pearson/Addison-Wesley,},
	year = {c1987.},
	address = {Boston :},
	edition = {3rdth ed.},
	note = {Eighth ed. also published under title: A problem solving approach to mathematics for elementary school teachers.}
}