APA (7th ed.) Citation

Quirk, R., & Crystal, D. (1986). A comprehensive grammar of the English language. Longman.

Chicago Style (17th ed.) Citation

Quirk, Randolph, and David Crystal. A Comprehensive Grammar of the English Language. London [etc.]: Longman, 1986.

MLA (9th ed.) Citation

Quirk, Randolph, and David Crystal. A Comprehensive Grammar of the English Language. Longman, 1986.