APA (7th ed.) Citation

(1983). Challenges: A multi-media project for learners of English. Langenscheidt-Longman.

Chicago Style (17th ed.) Citation

Challenges: A Multi-media Project for Learners of English. München: Langenscheidt-Longman, 1983.

MLA (9th ed.) Citation

Challenges: A Multi-media Project for Learners of English. Langenscheidt-Longman, 1983.

Warning: These citations may not always be 100% accurate.