The British Secret Service that Fostered Escape and Evasion, 1939-1945, and Its American Counterpart. Bodley Head, 1979. Little, Brown, 1980. Fight Another Day. Langley headed a section of MI 9, but actually worked for MI 6 for most of the war.
Safe Houses Are Dangerous.
Abson Books, 1989. Neave, who had first-hand experience at escaping from German prisons, for a time headed MI9's Room 900, the escape and evasion section for Western Europe. The Escape Room. Tower Publications, 1972. 2 . Saturday at MI9.