Cita APA

Knorr, K., & Verba, S. (1961). The international system: Theoretical essays. Princeton university press.

Chicago Edition Citation

Knorr, Klaus, i Sidney Verba. The International System: Theoretical Essays. USA: Princeton university press, 1961.

Cita MLA

Knorr, Klaus, i Sidney Verba. The International System: Theoretical Essays. Princeton university press, 1961.