Cita APA (7a ed.)

Parkin, M., & Spencer, D. E. (1990). Economics: Study guide. Addison-Wesley.

Cita Chicago Style (17a ed.)

Parkin, Michael, y David E. Spencer. Economics: Study Guide. Reading, Mass: Addison-Wesley, 1990.

Cita MLA (9a ed.)

Parkin, Michael, y David E. Spencer. Economics: Study Guide. Addison-Wesley, 1990.