@book{31492,
	author = {Elton, Edwin J.},
	title = {Modern portfolio theory and investment analysis /},
	publisher = {J. Wiley },
	year = {c2003.},
	address = {New York },
	edition = {6a ed.},
	url = {http://catdir.loc.gov/catdir/description/wiley037/2002024598.html}
}