@book{262104,
	author = {Salas, Saturnino L., and Etgen, Garret J., 1937-},
	title = {Calculus :},
	publisher = {Editorial Reverté,},
	year = {[2002]},
	address = {Barcelona :},
	edition = {4a edición.},
	url = {https://www.digitaliapublishing.com/a/67932/}
}