Boyd, E. (2009). Premium: C1 level (Coursebook). Harlow (England): Pearson education limited.
Trích dẫn kiểu ChicagoBoyd, Elaine. Premium: C1 Level (Coursebook). Harlow (England): Pearson education limited, 2009.
Deismireacht MLABoyd, Elaine. Premium: C1 Level (Coursebook). Harlow (England): Pearson education limited, 2009.
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