You means sources other than my experience in the USAF from Oct 1978 thru Mar 2000,
and my brother's experience in Tech Control, USAF from 1979 through 1986, and his coordination in Europe about some of the message traffic he was monitoring?
Oh, my brother was also on the ground as a radio operator with coded message traffic during
Operation Eagle Claw
Most of that information is classified, but some of it might be found in the Moscow archives and the German archives.
No, my sources are personal and not releasable.