@book{13438,
	author = {Block, Mark P.},
	title = {The encyclopedia of modern marbles, spheres & orbs /},
	publisher = {Schiffer,},
	year = {c2005.},
	address = {Atglen, PA :},
	url = {http://www.loc.gov/catdir/toc/ecip0513/2005015142.html}
}