APA (7th ed.) Citation

Chadwick, N. K. (1970). The Celts. Penguin Books.

Chicago Style (17th ed.) Citation

Chadwick, Nora K. The Celts. Harmondsworth, Eng.: Penguin Books, 1970.

MLA (8th ed.) Citation

Chadwick, Nora K. The Celts. Penguin Books, 1970.

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