Johnson, C. (2002). Pre-Intermediate Business English: Test file. Pearson Education.
Lua i Stíl Chicago (17ú heag.)Johnson, Christine. Pre-Intermediate Business English: Test File. Essex: Pearson Education, 2002.
Lua MLA (9ú heag.)Johnson, Christine. Pre-Intermediate Business English: Test File. Pearson Education, 2002.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.