Cita APA

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

Chicago Style Citation

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

Cita MLA

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

Atenció: Aquestes cites poden no estar 100% correctes.