Columbia subject headings:
Poland--Politics and government--1918-1945.
Socialism--Poland--History--20th century.
Harvard subject headings:
Poland--Politics and government--1918-1945
Socialism--Poland--20th century.
Socialism--Poland--History--20th century.
Princeton subject headings:
Poland--Politics and government--1918-1945.
Socialism--Poland--History--20th century.