@book{64440,
	author = {Beth, Thomas and Jungnickel, D.},
	title = {Design theory /},
	publisher = {Cambridge University Press,},
	year = {1999},
	series = {Encyclopedia of mathematics and its applications ;},
	address = {Cambridge, U.K. ;},
	edition = {2nd ed.},
	url = {http://www.loc.gov/catdir/toc/cam027/98029508.html}
}