@book{111170,
	author = {Van de Walle, John A.},
	title = {Teaching student-centered mathematics. Grades 3-5},
	publisher = {Pearson/Allyn and Bacon},
	year = {2006},
	series = {Van de Walle professional mathematics series ;},
	address = {Boston, MA},
	edition = {. ed.},
	url = {00001c/00001cc5.jpg}
}