APA (7th ed.) Citation

Van Valkenburg, S. (1943). Elements of political geography. Prentice-Hall.

Chicago Style (17th ed.) Citation

Van Valkenburg, Samuel. Elements of Political Geography. New York: Prentice-Hall, 1943.

MLA (9th ed.) Citation

Van Valkenburg, Samuel. Elements of Political Geography. Prentice-Hall, 1943.