APA-viite

Friedman, T. L. (2005). world is flat: A brief history of the globalized world in the 21st century. Penguin.

Chicago-tyylinen lähdeviittaus

Friedman, Thomas L. World Is Flat: A Brief History of the Globalized World in the 21st Century. England: Penguin, 2005.

MLA-viite

Friedman, Thomas L. World Is Flat: A Brief History of the Globalized World in the 21st Century. Penguin, 2005.