Columbia subject headings:
Harvard subject headings:
Germans--Political activity--Silesia, Upper (Poland and Czech Republic)
Polish people--Political activity--Silesia, Upper (Poland and Czech Republic)
Silesia, Upper (Poland and Czech Republic)--Politics and government--20th century.
Princeton subject headings:
Germans--Political activity--Silesia, Upper (Poland and Czech Republic).
Polish people--Political activity--Silesia, Upper (Poland and Czech Republic).
Silesia, Upper (Poland and Czech Republic)--Politics and government--20th century.