APA aipamena

O'Connell, S. (2010). Focus on IELTS. Harlow, England: Pearson Education.

Chicago Style aipamena

O'Connell, Sue. Focus On IELTS. Harlow, England: Pearson Education, 2010.

MLA aipamena

O'Connell, Sue. Focus On IELTS. Harlow, England: Pearson Education, 2010.

Kontuz: berrikusi erreferentzia hauek erabili aurretik.