@book{219434,
	author = {Sansone, Carol. and ebrary, Inc.},
	title = {Intrinsic and extrinsic motivation},
	publisher = {Academic Press,},
	year = {c2000.},
	series = {Educational psychology series},
	address = {San Diego :},
	url = {http://site.ebrary.com/lib/rucke/Doc?id=10190968}
}