APA aipamena

(2006).  Focus on grammar 4. An integrated skills approach.  Pearson Longman.

Chicago Style aipamena

 Focus On Grammar 4. An Integrated Skills Approach.  Pearson Longman, 2006.

MLA aipamena

 Focus On Grammar 4. An Integrated Skills Approach.  Pearson Longman, 2006.

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