A file of signals intelligence reports, messages, and correspondence issued by the Government Code and Cypher School and sent by the head ('C') of the Secret Intelligence Service (MI6) to the Prime Minister, Winston Churchill. This file includes the following reports on the Russian Front: a report for March 22 (on Russian attacks); a fragment of a ground forces report for March 22; a German 4th Army report for March 22; on the Russian fronts: a German 13th Army report for March 22; a German 46th Panzer Corps report of March 22; and a German 54th Army Corps report of March 22.