Diamond, j. (1999). Guns, Germs, and Steel. Norton.
Dyfyniad Arddull ChicagoDiamond, jared. Guns, Germs, and Steel. New York: Norton, 1999.
Dyfyniad MLADiamond, jared. Guns, Germs, and Steel. Norton, 1999.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.