Columbia subject headings:
Europe, Central--Politics and government--20th century--Congresses.
Europe, Eastern--Politics and government--20th century--Congresses.
European Union--Europe, Central--Congresses.
European Union--Europe, Eastern--Congresses.
European cooperation--Congresses.
European federation--Congresses.
Harvard subject headings:
Europe, Central--Politics and government--20th century--Congresses.
Europe, Eastern--Politics and government--20th century--Congresses.
European Union--Europe, Central--Congresses.
European Union--Europe, Eastern--Congresses.
European cooperation--Congresses.
European federation--Congresses
Princeton subject headings:
Europe, Central--Politics and government--20th century--Congresses.
Europe, Eastern--Politics and government--20th century--Congresses.
European Union--Europe, Central--Congresses.
European Union--Europe, Eastern--Congresses.
European cooperation--Congresses.
European federation--Congresses.