bug#24520: 25.1.50; calccard.tex has somewhat unclear licensing

[Eli Zaretskii <eliz@gnu.org>]

Ping!  Richard, I need your guidance as to how to proceed with this
issue.

> Date: Mon, 10 Oct 2016 13:38:56 +0300
> From: Eli Zaretskii <eliz@gnu.org>
> Cc: 24520@debbugs.gnu.org
> 
> > From: naesten@gmail.com
> > Date: Fri, 23 Sep 2016 14:58:22 -0400
> > 
> > 
> > Evaluate:
> > 
> >   (find-file (expand-file-name "refcards/calccard.tex" data-directory))
> > 
> > Now search for "Copyright" in the resulting buffer.  The first occurance
> > is as part of the usual GPLv3 boilerplate, just a bit further into the
> > file than is usual.  The second occurance precees a somewhat less clear
> > license grant:
> > 
> > > \def\copyrightnotice{
> > > \vskip 1ex plus 2 fill\begingroup\small
> > > \centerline{Copyright \copyright\ \year\ Free Software Foundation, Inc.}
> > > \centerline{designed by Dave Gillespie and Stephen Gildea,}
> > > \centerline{for GNU Emacs Calc.}
> > >
> > > Permission is granted to make and distribute copies of
> > > this card provided the copyright notice and this permission notice
> > > are preserved on all copies.
> > >
> > > %For copies of the GNU Emacs Calc manual, write to the Free Software
> > > %Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston,
> > > %MA 02110-1301, USA.
> > > %
> > > \endgroup}
> > 
> > So, we have two license grants that'd seem to apply to this file,
> > 
> >  (a) the usual GPLv3-or-later boilerplate
> >  
> >  (b) a brief, custom grant that doesn't explicitly permit modification
> > 
> > Also note that only (b) appears on the actual card; I don't think
> > there's even enough room on the card to fit (a).
> > 
> > Its not really clear what the licensing of this file is meant to be, but
> > I think it would be simplest to:
> > 
> >  (a) drop the GPLv3 licensing on this file, or explicitly use a dual
> >      license/GPL exception to unambiguously permit distribution with
> >      just the brief grant
> >     
> >  (b) add "in modified or unmodified form" to, and possibly remove "and
> >      this permission notice" from, said brief grant
> > 
> >  (c) mention the filename "calccard.tex" so people recieving it
> >      out-of-context can find the source easily
> > 
> > (Aside: the commented-out FSF address seems kind of useless nowadays...)
> 
> Richard, could you please tell what should be done about this issue?
> 
> TIA