Parkin, M., Powell, M., & Matthews, K. (2008). Economics (Seventh edition.). Addison-Wesley.
Lua i Stíl Chicago (17ú heag.)Parkin, Michael, Melanie Powell, agus Kent Matthews. Economics. Seventh edition. Harlow, England ; Boston, MA: Addison-Wesley, 2008.
Lua MLA (8ú heag.)Parkin, Michael, et al. Economics. Seventh edition. Addison-Wesley, 2008.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.