APA (7th ed.) Citation

Key, V. O. (1958). Politics, parties and pressure groups (4th edition.). Crowell.

Chicago Style (17th ed.) Citation

Key, Valdimer Orlando. Politics, Parties and Pressure Groups. 4th edition. New York: Crowell, 1958.

MLA (9th ed.) Citation

Key, Valdimer Orlando. Politics, Parties and Pressure Groups. 4th edition. Crowell, 1958.