Booulding, K. E. (1964). The meaning of the Twentieth Century. Higginbothams.
Dyfyniad Arddull ChicagoBooulding, Kenneth E. The Meaning of the Twentieth Century. Madras: Higginbothams, 1964.
Dyfyniad MLABooulding, Kenneth E. The Meaning of the Twentieth Century. Higginbothams, 1964.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.