Columbia subject headings:
Germany. Heer. Wehrkreis X. Abwehrstelle--History.
Hamburg Region (Germany)--History.
Intelligence service--Germany--Hamburg Region--History--20th century.
Military intelligence--Germany--Hamburg Region--History--20th century.
World War, 1939-1945--Secret service--Germany--Hamburg Region.
Harvard subject headings:
Germany. Heer. Wehrkreis X. Abwehrstelle--History.
Hamburg Region (Germany)--History.
Intelligence service--Germany--Hamburg Region--History--20th century.
Military intelligence--Germany--Hamburg Region--History--20th century.
World War, 1939-1945--Secret service--Germany--Hamburg Region.
Princeton subject headings:
Espionage--Germany--History--20th century.
Germany--Politics and government--1933-1945.
Germany. Heer. Wehrkreis X. Abwehrstelle--History.
Hamburg (Germany)--History.
Secret service--Germany--Hamburg--History--20th century.