Cornelsen. (2009). Interactive language course Business English: Negotiations. Tp.HCM: Tổng hợp Tp.Hcm; Công ty TNHH Nhân Trí Việt.
Παραπομπή Chicago StyleCornelsen. Interactive Language Course Business English: Negotiations. Tp.HCM: Tổng hợp Tp.Hcm; Công ty TNHH Nhân Trí Việt, 2009.
Παραπομπή MLACornelsen. Interactive Language Course Business English: Negotiations. Tp.HCM: Tổng hợp Tp.Hcm; Công ty TNHH Nhân Trí Việt, 2009.
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