Slice(OrderBy(Project(Extend(Extend(Extend(AggregationJoin(Aggregation(??agg1: ?artist, SAMPLE,
                                                           {},
                                                           G1=Group((?artist),
                                                              BGP( ?s <http://purl.org/net/ns/ext/moma#hasArtist> ?artist .
                                                               ?artist <http://schema.org/name> ?name))),
                                           Aggregation(??agg2: ?name, SAMPLE,
                                           {}, G1),
                                           Aggregation(??agg3: ?s, COUNT,
                                           {}, G1)),
                                           ?artist,
                                           ??agg1),
                                    ?name,
                                    ??agg2),
                             ?count,
                             ??agg3),
                      {?artist, ?name, ?count}), (desc (?count))),
      0,
      50)