Slice(Project(Filter((?premarkdown != ?postmarkdown),
                     Join(Graph(<http://markdownclean.example.org/>,
                                BGP( ?term <http://www.w3.org/2000/01/rdf-schema#comment> ?postmarkdown)),
                          Graph(<http://nomarkdowncleanyet.example.org/>,
                                BGP( ?term <http://www.w3.org/2000/01/rdf-schema#comment> ?premarkdown)))),
              {?premarkdown, ?postmarkdown}),
      0,
      10000)