Columbia subject headings:
America--Relations--Europe.
America.
Conference on Freedom of Communications and Transit (1st : 1921 : Barcelona)
Europe--Relations--America.
League of Nations.
Transportation--Law and legislation.
Harvard subject headings:
America--Politics and government.
America--Relations--Europe.
Conference on Freedom of Communications and Transit (1st : 1921 : Barcelona)
Europe--Relations--America.
League of Nations
Transportation--Law and legislation
Princeton subject headings: