Columbia subject headings:
Harvard subject headings:
Europe, Eastern--Social conditions--Congresses.
Urbanization--Europe, Eastern--Congresses.
Princeton subject headings:
Cities and towns--Europe, Central--Congresses.
Cities and towns--Europe, Eastern--Congresses.
City and town life--Europe, Central--Congresses.
City and town life--Europe, Eastern--Congresses.
Urbanization--Europe, Central--Congresses.
Urbanization--Europe, Eastern--Congresses.