Spencer, F. (1967). History of the World in the Twentieth Century. Pan Books.
Dyfyniad Arddull ChicagoSpencer, Frank. History of the World in the Twentieth Century. London: Pan Books, 1967.
Dyfyniad MLASpencer, Frank. History of the World in the Twentieth Century. Pan Books, 1967.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.