DOEACC Society. (2001). Quanbook `O` level: Model questions Vol III Business systems...... BPB.
Chicago-viite (17. p.)DOEACC Society. Quanbook `O` Level: Model Questions Vol III Business Systems...... New Delhi: BPB, 2001.
MLA-viite (9. p.)DOEACC Society. Quanbook `O` Level: Model Questions Vol III Business Systems...... BPB, 2001.
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