Cita APA (7th ed.)
Pfaltzgraff, R. L. (1969). Politics and the international system. Lippincott.
Cita Chicago (17th ed.)
Pfaltzgraff, Robert L. Politics and the International System. Philadelphia: Lippincott, 1969.
Cita MLA (9th ed.)
Pfaltzgraff, Robert L. Politics and the International System. Lippincott, 1969.
Atenció: Aquestes cites poden no estar 100% correctes.