Update

In Decoding Prime Minister Chamberlain’s messages I had said that ‘The source for this information is listed as IF-132 ‘Das Forschungsamt des Luftfahrtminsteriums - Hq USFET Weekly Intelligence summary # 12, 4 Oct. 1945’ . Unfortunately I do not have this document’.

Now that I found it I added the relevant page that refers to the communications of Chamberlain. Unfortunately there are no details given nor is the source identified.

File IF-132 ‘Das Forschungsamt des Luftfahrtminsteriums’ has been uploaded to my Ticom folder.