techno.md

@@ -15,13 +15,17 @@
 ### Data Management System
 * Small distributed relational databases: PostgreSQL
 * SPARQL endpoint to query the data
-* Mapping of relational data to RDF :100: ([R2RML implementations] from the [RDB2RDF Working Group]):
-  * [D2RQ] (Java)
-  * [R2D2] (PHP)
-  * [OpenLink Virtuoso] (C)
-  * [RDF4J] (aka Sesame) + [r2rml-api-rdf4j-bridge] (Java)
-  * [Allegrograph] (Common Lisp)
-  * [MarkLogic] (C++)
+* Mapping of relational data to RDF:
+  * 2 W3C recommandations from the [RDB2RDF Working Group]:
+    1. [Direct Mapping]: Mapping RDB to RDF
+    2. [R2RML]: RDB to RDF Markup Language
+  * [R2R implementations]:
+    * [D2RQ] (Java)
+    * [R2D2] (PHP)
+    * [OpenLink Virtuoso] (C)
+    * [RDF4J] (aka Sesame) + [r2rml-api-rdf4j-bridge] (Java)
+    * [Allegrograph] (Common Lisp)
+    * [MarkLogic] (C++)
 
 ### Web Server
   * [Apache HTTP Server]
@@ -58,7 +62,9 @@
 
 [NixOS]:https://nixos.org/
 [postgresql]:https://www.postgresql.org/
-[r2rml implementations]:https://www.w3.org/2001/sw/rdb2rdf/wiki/Implementations
+[R2RML]:https://www.w3.org/TR/r2rml/
+[Direct Mapping]:https://www.w3.org/TR/rdb-direct-mapping/
+[R2R implementations]:https://www.w3.org/2001/sw/rdb2rdf/wiki/Implementations
 [rdb2rdf working group]:https://www.w3.org/2001/sw/rdb2rdf/
 [d2rq]:http://d2rq.org/
 [r2d2]:http://aksw.org/Projects/R2D2.html