APA (7th ed.) Citation

Eckersley, C. E. (1960). Key to the Exercises in a comprehensive english grammar. Longmans.

Chicago Style (17th ed.) Citation

Eckersley, C. E. Key to the Exercises in a Comprehensive English Grammar. B. m: Longmans, 1960.

MLA (9th ed.) Citation

Eckersley, C. E. Key to the Exercises in a Comprehensive English Grammar. Longmans, 1960.

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