@book{34191,
	author = {Stewart, David W. and Shamdasani, Prem N.},
	title = {Focus groups :},
	publisher = {SAGE Publications,},
	year = {c2007.},
	address = {Thousand Oaks :},
	edition = {2a ed.},
	url = {http://www.loc.gov/catdir/toc/ecip0610/2006009180.html}
}