@book{10656,
	author = {Kreyszig, Erwin. and Kreyszig, Herbert.},
	title = {Advanced engineering mathematics },
	publisher = {National Book Foundation, NUST},
	year = {c2011.},
	address = {Islamabad},
	edition = {10th ed.},
	url = {http://www.loc.gov/catdir/enhancements/fy1114/2011287100-d.html}
}