Columbia subject headings:
Socialism--Germany--History--20th century.
Sozialdemokratische Partei Deutschlands.
Working class--Political activity--Germany--History.
Harvard subject headings:
Gesellschaft für Soziale Reform (Berlin, Germany)
Labor and laboring classes--Political activity--Germany--History.
Socialism--Germany--20th century.
Sozialdemokratische Partei Deutschlands
Working class--Germany--Political activity--History.
Princeton subject headings:
Gesellschaft für Soziale Reform.
Socialism--Germany--History--20th century.
Working class--Germany--Political activity--History.