@book{642,
	author = {Jellen, Hans G. and Verduin, John R.},
	title = {Handbook for differential education of the gifted :},
	publisher = {Southern Illinois University Press,},
	year = {c1986.},
	address = {Carbondale :},
	url = {http://www.loc.gov/catdir/enhancements/fy0743/85027703-b.html}
}