Columbia subject headings:
Harvard subject headings:
Carthusians--Germany--Prussia--History--Sources--Early works to 1800.
Carthusians--Poland--History--Sources--Early works to 1800.
Catholic Church--Foreign relations--Poland--Sources--Early works to 1800.
Germany--Foreign relations--Poland--Sources.
Poland--Foreign relations--Germany--Sources.
Princeton subject headings:
Germany--Foreign relations--Poland--Sources.
Poland--Foreign relations--Germany--Sources.