Project(OrderBy(LeftJoin(LeftJoin(LeftJoin(LeftJoin(LeftJoin(Join(BGP( ?topic <http://purl.org/dc/terms/title> ?title .
                                                                   ?topic <http://www.w3.org/ns/prov#wasDerivedFrom> ?origin .
                                                                   ?topic <http://dydra.com/cms/image> ?image),
                                                             Project(Extend(Extend(AggregationJoin(Aggregation(??agg1: ?topic, SAMPLE,
                                                                                                   {},
                                                                                                   G1=Group((?topic),
                                                                                                      BGP( ?topic <http://www.w3.org/1999/02/22-rdf-syntax-ns#type> <http://dydra.com/cms/Topic> .
                                                                                                       ?topic <http://dydra.com/cms/class> ?eachClass))),
                                                                                   Aggregation(??agg2: ?eachClass, GROUP_CONCAT,

                                                                                   <KEYWORD/SEPARATOR>, G1)),
                                                                            ?topic,
                                                                            ??agg1),
                                                                     ?class,
                                                                     ??agg2),
                                                             {?topic, ?class})),
                                                    BGP( ?topic <http://purl.org/dc/terms/abstract> ?abstract)),
                                           BGP( ?topic <http://purl.org/dc/terms/description> ?description)),
                                           BGP( ?topic <http://purl.org/dc/terms/date> ?date)),
                                  BGP( ?topic <http://purl.org/dc/terms/accessRights> ?rights)),
                         BGP( ?topic <http://purl.org/dc/terms/format> ?format)), (desc (?date))),
        {?topic, ?title, ?image, ?class, ?origin, ?description, ?abstract, ?date, ?rights, ?format})