@book{100981,
	author = {O'Callaghan Muñoz, Xavier. and Pedreira Andrade, Antonio.},
	title = {Introducción al derecho y derecho civil patrimonial},
	publisher = {Editorial Centro de Estudios R. Areces},
	year = {1993.},
	address = {Madrid},
	edition = {2 ed.}
}