@book{2357,
	author = {Gregg, Michael B. and Gregg, Michael B.},
	title = {Field epidemiology /},
	publisher = {Oxford University Press,},
	year = {2008.},
	address = {Oxford ;},
	edition = {3rd ed.},
	url = {http://www.loc.gov/catdir/toc/ecip081/2007040284.html}
}