APA (7th ed.) Citation

Duignan, B. (2013). Political systems, structures, and functions. Britannica Educational Pub. in association with Rosen Educational Services.

Chicago Style (17th ed.) Citation

Duignan, Brian. Political Systems, Structures, and Functions. New York, NY: Britannica Educational Pub. in association with Rosen Educational Services, 2013.

MLA (9th ed.) Citation

Duignan, Brian. Political Systems, Structures, and Functions. Britannica Educational Pub. in association with Rosen Educational Services, 2013.