Cita APA (7a ed.)

Barraclough, G. (1978). An introduction to contemporary history. Penguin Books.

Cita Chicago Style (17a ed.)

Barraclough, Geoffrey. An Introduction to Contemporary History. Harmondsworth [etc.]: Penguin Books, 1978.

Cita MLA (9a ed.)

Barraclough, Geoffrey. An Introduction to Contemporary History. Penguin Books, 1978.