Worthington, I. (2000). The business environmentIan Worthington, Chris Britton. Pearson Education.
Lua i Stíl Chicago (17ú heag.)Worthington, Ian. The Business EnvironmentIan Worthington, Chris Britton. Pearson Education, 2000.
Lua MLA (8ú heag.)Worthington, Ian. The Business EnvironmentIan Worthington, Chris Britton. Pearson Education, 2000.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.