Cita APA (7a ed.)

Douglas, E. S., Girimonti, S., & Samuel, J. (2019). C1 and now you're speaking. Editorial Tébar Flores.

Cita Chicago Style (17a ed.)

Douglas, Elisabeth S., Silvia Girimonti, y Julia Samuel. C1 and Now You're Speaking. Madrid: Editorial Tébar Flores, 2019.

Cita MLA (9a ed.)

Douglas, Elisabeth S., et al. C1 and Now You're Speaking. Editorial Tébar Flores, 2019.