@book{37505,
	author = {Schopenhauer, Arthur and Unamuno, Miguel de},
	title = {Sobre la voluntad en la naturaleza / },
	publisher = {Ediciones Altaya ,  },
	year = {1994.},
	series = {Grandes obras del pensamiento},
	address = {España : },
	note = {Incluye índice. }
}