Columbia subject headings:
Elections--Europe--History--Congresses.
Europe--Politics and government--Congresses.
Voting--Europe--History--Congresses.
Harvard subject headings:
Elections--Europe--History--Congresses.
Europe--Politics and government--Congresses.
Voting--Europe--History--Congresses.
Princeton subject headings:
Elections--Europe--History--Congresses.
Europe--Politics and government--Congresses.
Voting--Europe--History--Congresses.