Columbia subject headings:
Elite (Social sciences)--Germany, Northern--History--Congresses.
Elite (Social sciences)--Netherlands--History--Congresses.
Middle class--Germany, Northern--History--Congresses.
Middle class--Netherlands--History--Congresses.
Harvard subject headings:
Elite (Social sciences)--Germany--History--Congresses.
Elite (Social sciences)--Netherlands--History--Congresses.
Princeton subject headings:
Elite (Social sciences)--Germany, Northern--History.
Elite (Social sciences)--Netherlands--History.
Germany, Northern--Social conditions.
Middle class--Germany, Northern--History.
Middle class--Netherlands--History.
Netherlands--Social conditions.