Columbia subject headings:
Europe--History--1918-1945--Congresses.
Europe--Politics and government--1918-1945--Congresses.
Utopias--Europe--History--20th century--Congresses.
Harvard subject headings:
Europe--Politics and government--1918-1945--Congresses.
Utopias--Congresses
Princeton subject headings:
Europe--Politics and government--1918-1945--Congresses.
Utopias--Congresses.