Columbia subject headings:
Argentina--Foreign relations--Paraguay.
Argentina--Foreign relations--Uruguay.
Paraguay--Foreign relations--Argentina.
Paraguay--Foreign relations--Uruguay.
Uruguay--Foreign relations--Argentina.
Uruguay--Foreign relations--Paraguay.
Harvard subject headings:
Argentina--Foreign relations--Paraguay.
Argentina--Foreign relations--Uruguay.
Paraguay--Foreign relations--Argentina.
Paraguay--Foreign relations--Uruguay.
Uruguay--Foreign relations--Argentina.
Uruguay--Foreign relations--Paraguay.
Princeton subject headings: