@book{9779,
	author = {Hartup, Willard W. and University of Minnesota.},
	title = {Child psychology in retrospect and prospect :},
	publisher = {L. Erlbaum,},
	year = {2002.},
	series = {The Minnesota symposia on child psychology ;},
	address = {Mahwah, N.J. :},
	url = {http://www.loc.gov/catdir/enhancements/fy0662/2001040929-d.html}
}