Cita APA (7th ed.)

Shirreffs B. Brett & Conway D. Darren. (2011). On Course for IELTS: Student's Book (2nd ed.). Victoria, Oxford University Press, 2011.

Cita Chicago (17th ed.)

Shirreffs B. Brett i Conway D. Darren. On Course for IELTS: Student's Book. 2nd ed. Victoria, Oxford University Press, 2011, 2011.

Cita MLA (9th ed.)

Shirreffs B. Brett i Conway D. Darren. On Course for IELTS: Student's Book. 2nd ed. Victoria, Oxford University Press, 2011, 2011.