Friedman, T. L. (2005). The world is flat: A brief history of the twenty-first century. Farrar, Straus and Giroux.
Dyfyniad Arddull ChicagoFriedman, Thomas L. The World Is Flat: A Brief History of the Twenty-first Century. New York: Farrar, Straus and Giroux, 2005.
Dyfyniad MLAFriedman, Thomas L. The World Is Flat: A Brief History of the Twenty-first Century. Farrar, Straus and Giroux, 2005.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.