docs: def get_sigla(self, work):
          """Returns a list of all of the sigla for `work`.
  
          :param work: name of work
          :type work: `str`
          :rtype: `list` of `str`
  
          """
          return [os.path.splitext(os.path.basename(path))[0]
                  for path in glob.glob(os.path.join(self._path, work, '*.txt'))]