Columbia subject headings:
Intelligence officers--Great Britain--Biography.
Portland, Victor Frederick William Cavendish-Bentinck, Duke of, 1897-
Statesmen--Great Britain--Biography.
Harvard subject headings:
Intelligence officers--Great Britain--Biography.
Portland, Victor Frederick William Cavendish-Bentinck, Duke of, 1897-
Statesmen--Great Britain--Biography.
Princeton subject headings:
Intelligence officers--Great Britain--Biography.
Portland, Victor Frederick William Cavendish-Bentinck, Duke of, 1897-