Cita APA (7th ed.)

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

Cita Chicago (17th ed.)

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

Cita MLA (9th ed.)

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