APA (7th ed.) Citation

Cunliffe Barry. (1999). The ancient Celts. Penguin Books.

Chicago Style (17th ed.) Citation

Cunliffe Barry. The Ancient Celts. London: Penguin Books, 1999.

MLA (8th ed.) Citation

Cunliffe Barry. The Ancient Celts. Penguin Books, 1999.

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