APA (7th ed.) Citation

Barraclough, G. (1967). An introduction to contemporary history. Penguin Books.

Chicago Style (17th ed.) Citation

Barraclough, Geoffrey. An Introduction to Contemporary History. Madrid: Penguin Books, 1967.

MLA (9th ed.) Citation

Barraclough, Geoffrey. An Introduction to Contemporary History. Penguin Books, 1967.