@book{1506,
	author = {Bryman, Alan. and Cramer, Duncan,},
	title = {Quantitative data analysis with SPSS for Windows :},
	publisher = {Routledge,},
	year = {1997.},
	address = {London ;},
	url = {http://www.loc.gov/catdir/enhancements/fy0909/96007866-d.html}
}