Update README

Author: pchampin

README.md

@@ -1,6 +1,11 @@
 # rdf-tests
-Repository for the RDF Tests Community Group
+Repository for the [RDF Tests Community Group]
 
 To view (HTML) files can be [read directly](https://w3c.github.io/rdf-tests/).
 
 The index.html files are built using a Ruby tool-chain based on the corresponding manifest.ttl files. Update using `rake`. Requires Ruby, rdf-turtle and json-ld gems to be installed.
+
+Currently, the test suites for RDF ([rdf/](rdf/)) and SPARQL ([sparql/](sparql/)) are jointly managed by the [RDF Tests Community Group] and the [RDF & SPARQL Working Group].
+
+[RDF Tests Community Group]: https://www.w3.org/groups/cg/rdf-tests/
+[RDF & SPARQL Working Group]: https://www.w3.org/groups/wg/rdf-star/