Columbia subject headings:
Harvard subject headings:
Brain drain--Germany--History--20th century.
Nazis.
Secret service--United States--History--20th century.
Spies--Europe--Recruiting--History--20th century.
Spies--Recruiting--Europe--History--20th century.
United States--Emigration and immigration--History--20th century.
War criminals--Germany--Recruiting--History--20th century.
War criminals--Recruiting--Germany--History--20th century.
World War, 1939-1945--Collaborationists--Recruiting.
World politics--1945-
World politics--1945-1989
Princeton subject headings:
Brain drain--Germany--History--20th century.
Nazis.
Secret service--United States--History--20th century.
Spies--Europe--Recruiting--History--20th century.
United States--Emigration and immigration--History--20th century.
War criminals--Germany--Recruiting--History--20th century.
World War, 1939-1945--Collaborationists--Recruiting.
World politics--1945-1989.