APA-viite (7. p.)

Douglas, E. S., Girimonti, S., & Samuel, J. (2019). C1 skills training: The five, themed units give you extensive skills practice to up your level or prepare your exams. Editorial Tébar Flores.

Chicago-viite (17. p.)

Douglas, Elisabeth S., Silvia Girimonti, ja Julia Samuel. C1 Skills Training: The Five, Themed Units Give You Extensive Skills Practice to Up Your Level or Prepare Your Exams. Madrid, España: Editorial Tébar Flores, 2019.

MLA-viite (9. p.)

Douglas, Elisabeth S., et al. C1 Skills Training: The Five, Themed Units Give You Extensive Skills Practice to Up Your Level or Prepare Your Exams. Editorial Tébar Flores, 2019.

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