Cita APA (7th ed.)

Heck, G. W. (2006). Charlemagne, Muhammad, and the Arab roots of capitalism. De Gruyter.

Cita Chicago (17th ed.)

Heck, Gene W. Charlemagne, Muhammad, and the Arab Roots of Capitalism. Berlin ; New York: De Gruyter, 2006.

Cita MLA (9th ed.)

Heck, Gene W. Charlemagne, Muhammad, and the Arab Roots of Capitalism. De Gruyter, 2006.