@book{131211,
	author = {Simmons, George Finlay,},
	title = {Differential equations, with applications and historical notes /},
	publisher = {McGraw-Hill,},
	year = {c1991.},
	address = {New York :},
	edition = {2nd ed.},
	url = {http://www.loc.gov/catdir/description/mh022/90033686.html}
}