Typescript notes and copies of photographs, compiled by his nephew, Bruce O B Williams, relating to Cadogan's life and career, 1908-1998, including genealogical information and notes on bibliographic sources on the Chindit operations in Burma, 1943-1944 (Operations LONGCLOTH, Feb-Mar 1943 and THURSDAY, Mar 1944). Also, brief typescript notes on the life and military careers of Lt Ernest Llewellyn Williams, 160 Bde, Royal Field Artillery, 34 Div, Western Front, 1917-1918, and Maj Lewis Bernard Williams, Royal Artillery, World War Two, 1939-1945.

Photocopy of caricature of staff of HQ, second Chindit operation, Burma, 1944; photocopy of article by Brig Peter W Mead and Sir Robert Thompson on Maj Gen Orde Charles Wingate with related papers, 1978.