Cita APA (7th ed.)

Doff, A., Stirling, J., & Ackroyd, S. (2011). English unlimited: Advanced Teacher's Pack. C1 (1a. ed.). Cambridge University Press.

Cita Chicago (17th ed.)

Doff, Adrian, Johanna Stirling, i Sarah Ackroyd. English Unlimited: Advanced Teacher's Pack. C1. 1a. ed. Cambridge University Press, 2011.

Cita MLA (9th ed.)

Doff, Adrian, et al. English Unlimited: Advanced Teacher's Pack. C1. 1a. ed. Cambridge University Press, 2011.