Kahn, H., & Brown, W. M. (1977). The Next 200 years: A Scenario for America and the World.
Dyfyniad Arddull ChicagoKahn, Herman, and William Marte Brown. The Next 200 Years: A Scenario for America and the World. London, 1977.
Dyfyniad MLAKahn, Herman, and William Marte Brown. The Next 200 Years: A Scenario for America and the World. 1977.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.