Columbia subject headings:
Harvard subject headings:
Elite (Social sciences)--Congresses.
Michels, Robert, 1876-1936--Congresses.
Oligarchy--Congresses.
Political sociology--Congresses
Power (Social sciences)--Congresses
Princeton subject headings:
Democracy--Congresses.
Michels, Robert, 1876-1936. Zur Soziologie des Parteiwesens in der modernen Demokratie--Congresses.
Political parties--Congresses.