Cita APA (7th ed.)

Arnold, R. A. (2020). Economics (13th ed.). Cengage Learning.

Cita Chicago (17th ed.)

Arnold, Roger A. Economics. 13th ed. Boston, MA: Cengage Learning, 2020.

Cita MLA (9th ed.)

Arnold, Roger A. Economics. 13th ed. Cengage Learning, 2020.