anchor.diff:        )
       }
   }
  -
  +....
  ++
  +[[query_for_labels_of_classes_on_background_graph]]
  +.Listing 10. Obtain labels of the classes c1 c2 ... cn from the background graph
  +....
  +PREFIX rdfs: <http://www.w3.org/2000/01/rdf-schema#>
  +SELECT DISTINCT ?c ?label
  +WHERE {
  +      ?c rdfs:label ?label.
  +      filter (
  +        ?c IN (<c1>, <c2>, ..., <cn>)
  +      )
  +    }
  +}
   ....
   3.  Datatypes
   +
   If there is GRAPH clause being applied, we retrieve a list of datatypes using a query described in Listing
  -<<query_for_datatypes_on_a_graph, 8>>.
  +<<query_for_datatypes_on_a_graph, 11>>.
   +
   [[query_for_datatypes_on_a_graph]]
  -.Listing 8. Obtain the datatypes on a graph g
  +.Listing 11. Obtain the datatypes on a graph g
   ....
   SELECT DISTINCT (datatype(?o) AS ?ldt)
   FROM <g>
  
positive.code: +
  We assume all subjects of statements are things. If there is GRAPH clause being applied, we search invalid
  statement using a query described in Listing
  <<non_http_uri_subject, 10>>, and if nothing is found the endpoint
  satisfied this rule.
  +
  Note that we ignore Virtuoso specific graphs since Virtuoso contains a
  graph which contains invalid statements.
  +
  [[non_http_uri_subject]]
  .Listing 10. A Query for searching non-HTTP-URI subjects
  ....
  SELECT
    *
  
negative.code:   ))
  }
  LIMIT 1
  ....
  +
  [[non_http_uri_subject_on_background_graph]]
  .Listing 16. A Query for searching non-HTTP-URI subjects on the background graph
  ....
  SELECT
    *
  WHERE {
    filter (!regex(?s, "^http://", "i") && !isBLANK(?s) && ?g NOT IN (
      <http://www.openlinksw.com/schemas/virtrdf#>
    ))
  }
  LIMIT 1
  ....
  . When someone looks up a URI, provide useful information, using the
  standards (RDF*, SPARQL)
  +
  We assess this rule by obtaining a subject (URI) using a query described
  in Listing <<query_for_a_subject_on_a_graph, 17>> and accessing the URI via HTTP
  protocol. We assume that the endpoint is satisfied with the rule if the
  URI returns any data.
  +
  Note that we ignore Virtuoso specific graphs since Virtuoso contains a
  graph which contains invalid statements.
  +
  [[query_for_a_subject_on_a_graph]]
  .Listing 17. A Query for a Subject on a graph g
  ....
  SELECT
    ?s
  