Indeed the Unix manuals were available as printed
books. Volume One was
the manual pages and Volume Two the articles from /usr/doc.
I remember
seeing soft-cover bound copies of the 7th Edition manuals, ...
I think the next time this happened in the exact same
way was with the
"Unix Research System Tenth Edition" books published by
Saunders College
Publishing in 1990.
Those were the only two that were published as trade books. I still use
the 10th Ed regularly. The 7th Ed was a debacle. The publisher didn't
bother to send us galleys because they had printed straight from troff.
It turned out they did not have the full troff character set, and put
an @ sign in place of each missing character. The whole print run was
done before we saw a copy. Not knowing whether they ever fixed it, I'd
be interested to hear whether or not the botch made it to bookstores.
Doug