Columbia subject headings:
Paris (France)--History--Commune, 1871.
Socialism--Germany--History--19th century.
Working class--Germany--History--19th century.
Harvard subject headings:
Paris (France)--History--Commune, 1871.
Socialism--Germany--19th century.
Socialism--Germany--History--19th century
Working class--Germany--History--19th century
Princeton subject headings:
Labor movement--Germany--History--19th century.
Paris (France)--History--Commune, 1871.
Socialism--Germany--History--19th century.