Columbia subject headings:
Harvard subject headings:
North Rhine Westphalia (Germany. Landtag--History.
North Rhine-Westphalia (Germany)--Politics and government.
Sozialdemokratische Partei Deutschlands--History.
Princeton subject headings:
North Rhine-Westphalia (Germany)--Politics and government.
North Rhine-Westphalia (Germany). Landtag--History.
Sozialdemokratische Partei Deutschlands--History.