Yeah, other than the source: https://github.com/PDP-10/its/blob/master/src/sysen2/mldev.106 there's not a lot on it. That's typical of a lot of the innovative work done at the AI Lab, LCS, etc; they built some extraordinary tools, but to them they were just tools they used to work on their research, their _real_ work. So why bother to write that stuff up? So people who actually used them remember them, but other than that... Welcome to tomorrow, where everything gets re-invented, because everyone is too busy to waste time learning about the past. Noel