Cita APA

Pfaltzgraff, R. L. 1., & Pfaltzgraff, R. L. 1. (1972). Politics and the international system. (2. edition.). Philadelphia: J. B. Lippincott Company.

Citación estilo Chicago

Pfaltzgraff, Robert L. 1934-, y Robert L. 1934- Pfaltzgraff. Politics and the International System. 2. edition. Philadelphia: J. B. Lippincott Company, 1972.

Cita MLA

Pfaltzgraff, Robert L. 1934-, y Robert L. 1934- Pfaltzgraff. Politics and the International System. 2. edition. Philadelphia: J. B. Lippincott Company, 1972.