Columbia subject headings:
Poland--Social conditions.
Posen (Province)--History.
Harvard subject headings:
Polish people--Germany--Prussia
Poznań (Poland : Voivodeship)--History.
Prussia (Germany)--History--Revolution, 1848-1849.
Princeton subject headings:
Polish people--Germany--Prussia.
Poznań (Poland : Voivodeship)--History.
Prussia (Germany)--History--Revolution, 1848-1849.