@book{71828,
	author = {Szarota, Piotr and Szarota, Piotr},
	title = {La Sonrisa :},
	publisher = {Universitat Oberta de Catalunya, },
	year = {2011},
	address = {[Madrid, España] :},
	url = {https://public.digitaliapublishing.com/a/20343}
}