Columbia subject headings:
Harvard subject headings:
Germany--Politics and government--1789-1900.
Occupations--Poland--Poznań (Voivodeship)--History.
Poland--Politics and government--1796-1918
Polish people--Germany--Prussia--History.
Poznań (Poland : Voivodeship)--Commerce--History.
Poznań (Poland : Voivodeship)--Economic conditions.
Princeton subject headings:
Poland--Wielkopolska--Economic conditions.