Columbia subject headings:
Harvard subject headings:
Germans--Poland--Łódź--History--19th century--Congresses.
Germans--Poland--Łódź--History--20th century--Congresses.
Germans--Poland--Łódź--Social life and customs--Congresses.
Princeton subject headings:
Germans--Poland--Łódź--History--19th century--Congresses.
Germans--Poland--Łódź--History--20th century--Congresses.
Germans--Poland--Łódź--Social life and customs--Congresses.