Columbia subject headings:
Prisoners of war--Poland--History--20th century--Sources.
Prisoners of war--Soviet Union--History--20th century--Sources.
World War, 1939-1945--Prisoners and prisons, Russian--Sources.
Harvard subject headings:
Prisoners of war--Poland--History--20th century--Sources.
Prisoners of war--Soviet Union--History--Sources.
World War, 1939-1945--Prisoners and prisons, Soviet--Sources.
Princeton subject headings:
Prisoners of war--Poland--History--20th century--Sources.
Prisoners of war--Soviet Union--History--20th century--Sources.
World War, 1939-1945--Prisoners and prisons, Soviet--Sources.