Columbia subject headings:
Forced labor--Germany, Northern.
Nazi concentration camps--Germany.
World War, 1939-1945--Concentration camps--Germany, Northern.
Harvard subject headings:
Forced labor--Germany, Northern.
Forced labor--Germany--History--20th century
Nazi concentration camps--Germany
World War, 1939-1945--Concentration camps--Germany, Northern.
World War, 1939-1945--Conscript labor--Germany
Princeton subject headings:
Forced labor--Germany, Northern.
Nazi concentration camps--Germany.
World War, 1939-1945--Concentration camps--Germany, Northern.