Cita APA (7a ed.)

Bergonzi, B. (1970). The twentieth century. Barrie & Jenkins.

Cita Chicago Style (17a ed.)

Bergonzi, Bernard. The Twentieth Century. London: Barrie & Jenkins, 1970.

Cita MLA (9a ed.)

Bergonzi, Bernard. The Twentieth Century. Barrie & Jenkins, 1970.