Friedman, T. L. (2007). The world is flat: A brief history of the twenty-first century (Further updated and expanded.). Picador.
Dyfyniad Arddull ChicagoFriedman, Thomas L. The World Is Flat: A Brief History of the Twenty-first Century. Further updated and expanded. New York: Picador, 2007.
Dyfyniad MLAFriedman, Thomas L. The World Is Flat: A Brief History of the Twenty-first Century. Further updated and expanded. Picador, 2007.
Rhybudd: Mae'n bosib nad yw'r dyfyniadau hyn bob amser yn 100% cywir.