Parkin, M. (1998). Economics (4th ed.). Addison-Wesley.
Lua i Stíl Chicago (17ú heag.)Parkin, Michael. Economics. 4th ed. Reading, Mass.: Addison-Wesley, 1998.
Lua MLA (8ú heag.)Parkin, Michael. Economics. 4th ed. Addison-Wesley, 1998.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.