John Tonkovich,
Thanks for your comment.
Tom Scully,
I was interested in Ayers mostly because of his claim that the Bishop sketch looked like Campbell. I have looked into Ayers and it seems to me that many of his claims are speculative. I think it is likely that he mistook someone else in the CIA for Campbell. This could have been a mistake on his part or a purposeful deception engineered by a CIA person (who may have pointed "Campbell" out to Ayers) for unknown reasons. The same thing happened to David Phillips according to his book. Someone told him a certain individual was Angleton and he went on believing that for some time before discovering it was untrue. In any case, thanks for the interesting information.
BTW, have you ever looked into David Phillips' family background? I know Linda Minor has done some work in this area, but I am more interested in his parents, brothers and his children than I am going way back in time like she did. I am also interested in his wives, particularly his short-lived first marriage to Joan (or Jean) Hildebrandt.