In the "num" bibliography style, bibliography entries that get "et
al."ed (the author list is too long and "et al." is inserted) end up
with two full stops in a row.  Here's a minimal example:

  \setupbibtex[database=tmp]
  \setuppublications[alternative=num]

  \setuppublicationlist[artauthoretallimit=3, authoretaldisplay=3,
    editoretaldisplay=3, artauthoretaldisplay=3,
  %  authoretaltext={ et al},
  %  artauthoretaltext={ et al},
  ]

  \starttext

  Test \cite[Larkin:1980].

  \blank[big]

  \placepublications[criterium=text]

  \stoptext

(The tmp.bib file is attached.)  The bibliography entry is:

  [1] Jill Larkin, John McDermott and Dorothea P. Simon et al.. Expert and
  novice performance in solving physics problems. Science,
  208(4450):1335--1342, 1980.

The doubled full stop can be fixed by commenting in the two lines

  %  authoretaltext={ et al},
  %  artauthoretaltext={ et al},

Should these commented-in settings be the default for the "num" style
(because it'll always put one more full stop between the author list and
the title)?

Another workaround is never to use et al.  But that idea failed when I
had to cite the Nobel-Prize-winning gravity-wave paper ("Observation of
Gravitational Waves from a Binary Black Hole Merger").  It has, I think,
1000 authors!

-- 
-Sanjoy

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