Thompson's original paper used used the example espression: a(b|c)*d without any description of what it meant, so I take it that at the very least, that m

Thompson's original paper used used the example espression: a(b|c)*d without any description of what it meant, so I take it that at the very least, that much was borrowed from Kleene. I am having a hard time reading it, to see if anything else was implemented, as I am unfamiliar with Algol-60 or IBM 7094 assembly. He cites Kleene's paper, saying that he assumes the reader is familiar with regular expressions; I'd look at that paper and see what Kleene described, but I can't find a copy of that. Thompson also site a paper by Brzozowski. The abstract for that paper includes: "Kleene's regular expressions, which can be used for describing sequential circuits, were defined using three operators (union, concatenation and iterate)" Which I take to mean that Kleene only came up with the syntax expressed in the example expression at the beginning.