Columbia subject headings:
Cities and towns--Europe--History--20th century--Congresses.
Municipal government--Europe--History--20th century--Congresses.
Socialism--Europe--History--20th century--Congresses.
Harvard subject headings:
Cities and towns--Europe--History--20th century--Congresses.
Municipal government--Europe--History--20th century--Congresses.
Municipal ownership--Europe--History--Congresses.
Municipal services--Europe--History--Congresses.
Socialism--Europe--Congresses
Socialism--Europe--History--20th century--Congresses.
Princeton subject headings:
Municipal ownership--Europe--History--Congresses.
Municipal services--Europe--History--Congresses.
Socialism--Europe--History--Congresses.