@book{169094,
	author = {Steffe, Leslie P. and ebrary, Inc.},
	title = {Radical constructivism in action},
	publisher = {Falmer,},
	year = {2000.},
	series = {Studies in mathematics education series ;},
	address = {New York :},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10054179}
}