APA (7th ed.) Citation

Yorkey, R. (1978). English for international communication workbook. American Book.

Chicago Style (17th ed.) Citation

Yorkey, Richard. English for International Communication Workbook. American Book, 1978.

MLA (8th ed.) Citation

Yorkey, Richard. English for International Communication Workbook. American Book, 1978.

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