@book{204629,
	author = {Marks, John L. and Marks, John L.},
	title = {Teaching elementary school mathematics for understanding /},
	publisher = {McGraw-Hill,},
	year = {1975.},
	address = {New York :},
	edition = {4th ed.},
	note = {First ed. published in 1958 under title: Teaching arithmetic for understanding. Previous editions by J. L. Marks, C. R. Purdy, and L. B. Kinney.}
}