@book{4691,
	author = {Ziegler, Edward N.  and Ziegler, Ed},
	title = {Encyclopedia of environmental science and engineering, sixth edition /},
	publisher = {CRC Press,},
	year = {2012.},
	series = {Print version.},
	address = {[S.l.] :},
	edition = {6th ed.},
	url = {http://www.amazon.com/exec/obidos/ASIN/1439804427/chopacon}
}