🚀 go-pugleaf

(Our link from campus to the outside world was down for two weeks, and I
think this item died in the interim.  Apologies to those who have seen it.)

    In his book "Document Formatting and Typesetting on the UNIX System,"
(Summit, NJ: Silicon Press, 1986), Narain Gehani lists (pp.248-) "Recent
Enhancements to eqn."  His list of eight changes includes some -- multi-
character font names are now accepted -- which have been implemented on our
version (in System 5.2.2 Unix on a Vax 11/780), and some which have not been
implemented.
    One of the non-implemented changes is a file-inclusion capability, the
"include" instruction; another is printing equations using the appropriate
point size in footnotes.
    My questions are four:

1. Which versions of eqn include "include"?

2. Is there a version number attached to "eqn" copies? (and if so how can one
   access it?)

3. What is the most recent upgrade version of eqn (if eqn is so numbered)?

4. How can we obtain information about and upgrades of eqn and other DWB
   programs? (Our support staff are not optimistic that our UN*X licence fee
   entitles us to this information from AT&T automatically.)

    These queries are about eqn (the formula/equation specifying troff
preprocessor), but could equally well be about grap, pic, or tbl. 
(According to the RE string name in -mm, our mm is Release Level  16.29)