Parkin, M. (2014). Economics (11th ed.). Pearson.
Lua i Stíl Chicago (17ú heag.)Parkin, Michael. Economics. 11th ed. Boston: Pearson, 2014.
Lua MLA (8ú heag.)Parkin, Michael. Economics. 11th ed. Pearson, 2014.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.