@book{12219,
	author = {Piaget, Jean, and ebrary, Inc.},
	title = {The child's conception of physical causality},
	publisher = {Routledge,},
	year = {1999, c1930.},
	series = {Developmental psychology ;},
	address = {London :},
	note = {Originally published: London : Kegan Paul, Trench, Trubner, 1930.},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10017131}
}