Cita APA (7th ed.)

Derbyshire, J. D., & Derbyshire, I. (1989). Chambers political systems of the world. Chambers.

Cita Chicago (17th ed.)

Derbyshire, J. Denis, i Ian Derbyshire. Chambers Political Systems of the World. Edinburgh: Chambers, 1989.

Cita MLA (9th ed.)

Derbyshire, J. Denis, i Ian Derbyshire. Chambers Political Systems of the World. Chambers, 1989.