Gibbs, H. S., & Gyorgy, A. Problems in international relations.
Cita Chicago (17th ed.)Gibbs, Hubert St, i Andrew Gyorgy. Problems in International Relations.
Cita MLA (9th ed.)Gibbs, Hubert St, i Andrew Gyorgy. Problems in International Relations.
Atenció: Aquestes cites poden no estar 100% correctes.