(2017). Delta Academic Objectives - Listening and Note Taking Skills B2-C1 Coursebook with Audio CD. Stuttgart Klett Sprachen GmbH.
Chicago-viite (17. p.)Delta Academic Objectives - Listening and Note Taking Skills B2-C1 Coursebook with Audio CD. German: Stuttgart Klett Sprachen GmbH, 2017.
MLA-viite (9. p.)Delta Academic Objectives - Listening and Note Taking Skills B2-C1 Coursebook with Audio CD. Stuttgart Klett Sprachen GmbH, 2017.
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