APA Edition Citation

Derbyshire, J. D., & Derbyshire , I. A. (1999). Political systems of the world (3rd ed.). Helicon Publishing.

Chicago Edition Citation

Derbyshire, J. D., and I. A. Derbyshire. Political Systems of the World. 3rd ed. Oxford: Helicon Publishing, 1999.

MLA Edition Citation

Derbyshire, J. D., and I. A. Derbyshire. Political Systems of the World. 3rd ed. Helicon Publishing, 1999.