@book{6789,
	author = {Hasnain , S K },
	title = {Digital signal processing :},
	publisher = {TBS,},
	year = {2011.},
	series = {3rd edition.},
	address = {Karachi},
	edition = {3rd ed.},
	url = {http://www.amazon.com/exec/obidos/ASIN/B006X7SJAC/chopaconline-20}
}