APA aipamena

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

Chicago Style aipamena

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

MLA aipamena

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

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