I am currently writing an article about the Historia Augusta, which is so well-known for its use of fake documents. About one of these sources, Cordus, the author writes that he is unreliable. In other words, he has invented a source to disagree with. It’s a great joke. What I am trying to find out, is whether there are older parallels.
The only possibility I know of, is “Damis”, who is quoted in Philostratus‘ Life of Apollonius. Personally, I am not convinced that Damis is a fake source, but that is a completely different question. For the moment, I hope to discover (other) parallels to the SHA‘s joke.