Cita APA (7a ed.)

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

Cita Chicago Style (17a ed.)

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

Cita MLA (9a ed.)

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