APA (7 वां संस्करण) प्रशस्ति पत्र

(2017). Delta Academic Objectives - Listening and Note Taking Skills B2-C1 Coursebook with Audio CD. Stuttgart Klett Sprachen GmbH.

शिकागो शैली (17वां संस्करण) प्रशस्ति पत्र

Delta Academic Objectives - Listening and Note Taking Skills B2-C1 Coursebook with Audio CD. German: Stuttgart Klett Sprachen GmbH, 2017.

एमएलए (9वां संस्करण) प्रशस्ति पत्र

Delta Academic Objectives - Listening and Note Taking Skills B2-C1 Coursebook with Audio CD. Stuttgart Klett Sprachen GmbH, 2017.