Columbia subject headings:
Dissenters--Poland.
Opposition (Political science)--Poland.
Poland--Politics and government--20th century.
Harvard subject headings:
Dissenters--Poland--History--20th century.
Dissenters--Poland.
Left-wing extremists--Poland.
Opposition (Political science)--Poland--History--20th century.
Opposition (Political science)--Poland.
Poland--Politics and government--20th century
Political parties--Poland--History--20th century
Princeton subject headings: