DOEACC Society. (2001). Quanbook `O` level: Model questions Vol III Business systems...... BPB.
Lua i Stíl Chicago (17ú heag.)DOEACC Society. Quanbook `O` Level: Model Questions Vol III Business Systems...... New Delhi: BPB, 2001.
Lua MLA (9ú heag.)DOEACC Society. Quanbook `O` Level: Model Questions Vol III Business Systems...... BPB, 2001.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.