Douglas McIlroy <douglas.mcilroy@dartmouth.edu> wrote:

> > https://www.tuhs.org/Archive/Documentation/Manuals/Unix_4.0/Volume_1/C.1.2_NROFF_TROFF_Users_Manual.pdf
>
> Since PDF didn't exist in 1981, the document is either a scan or the
> result of a recent *roff run on ancient source. If it was made from
> source, it's an impressive testimonial to the longevity and stability
> of troff. Most probably it's a scan, in which case we owe many thanks
> to the public-spirited person who digitized this trove. Was it you,
> Arnold?
>
> Doug

It's a scan of photocpies I made from original printed documentation.
Matt Gilmore did the scanning; I had the paper on my shelf for ~ 40 years.

It was set on an Autologic APS-5, as one can see on the second page
of the table of contents file.

Arnold