Return a list of concepts or collections that should be displayed under this concept or collection.

        :param str id: A concept or collection id.
        :returns: A :class:`lst` of concepts and collections.

def get_children_display(self, id, **kwargs):
        """ Return a list of concepts or collections that should be displayed under this concept or collection.

        :param str id: A concept or collection id.
        :returns: A :class:`lst` of concepts and collections.
        """
        broader = 'broader'
        type_values = "((?Type = skos:Concept) || (?Type = skos:Collection))"

        query = """SELECT ?Subject ?Id ?Type ?Term (lang(?Term) as ?Lang)
                {
                ?Subject rdf:type ?Type;
                dc:identifier ?Id; skos:inScheme %s:; gvp:%s %s:%s;.
                OPTIONAL {
                  {?Subject xl:prefLabel [skosxl:literalForm ?Term]}
                          }
                FILTER(%s)
                }""" % (self.vocab_id, broader, self.vocab_id, id, type_values)

        ret= self._get_answer(query, **kwargs)
        language = self._get_language(**kwargs)
        sort = self._get_sort(**kwargs)
        sort_order = self._get_sort_order(**kwargs)
        return self._sort(ret, sort, language, sort_order == 'desc')