@book{912,
	author = {Haykin, Simon S. and Van Veen, Barry.},
	title = {Signals and systems /},
	publisher = {Wiley,},
	year = {c2002-2003.},
	address = {New York:},
	edition = {2nd ed.},
	note = {Includes index.},
	url = {http://www.loc.gov/catdir/description/wiley0310/2002027040.html}
}