APA (7th ed.) Citation

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

Chicago Style (17th ed.) Citation

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

MLA (9th ed.) Citation

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