> [I don't know where this came from, but I have to
> pass it on. Previous sender omitted, he doesn't know either.]
>
> The original author is David Moser; I originally saw it in one of
> Douglas Hofstadter's old Metamagical Themas columns in Scientific
> American (it's in ch. 2 of my anthology of those columns; no date
> is given for any of the columns but credits for the illustrations
> in that column give a copyright date of January 1982).
I first saw it in a bitnet archive called NutWorks. Great, similar
stuff.
http://www.pcuf.fi/~pjx/nutworks/
(Oops. The dates are later than '84.)