@book{12757,
	author = {Cohen, David, and ebrary, Inc.},
	title = {The development of play},
	publisher = {Routledge,},
	year = {1993.},
	series = {Concepts in developmental psychology},
	address = {London ;},
	edition = {2nd ed.},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10017790}
}