@book{11,
	author = {Keith, Lawrence H.,},
	title = {Principles of environmental sampling /},
	publisher = {American Chemical Society,},
	year = {c1996.},
	address = {Washington, DC :},
	edition = {2nd ed.},
	note = {H.B},
	url = {http://www.loc.gov/catdir/enhancements/fy0605/96009386-d.html}
}