--- a/rdf-primer/index.html	Mon Dec 02 16:37:11 2013 +0100
+++ b/rdf-primer/index.html	Mon Dec 02 17:26:47 2013 +0100
@@ -292,7 +292,7 @@
     predicates form the arcs. </p> 
 
     <figure>
-      <img src="example-graph.jpg" width="60%"
+      <img src="example-graph.jpg" width="75%"
                 alt="Informal graphs of the sample triples">
       <figcaption>Informal graph of the sample triples</figcaption>
     </figure>
@@ -345,16 +345,15 @@
       <div class="example"><a href="http://data.europeana.eu/item/04802/243FA8618938F4117025F17A8B813C5F9AA4D619">http://data.europeana.eu/item/04802/243FA8618938F4117025F17A8B813C5F9AA4D619</a></div>
 
     <figure>
-      <img src="example-graph-iris.jpg" width="60%"
+      <img src="example-graph-iris.jpg" width="75%"
                 alt="Informal graphs of the sample triples, with IRIs">
       <figcaption>Informal graph of the sample triples, with IRIs</figcaption>
     </figure>
 
-    <!--p class="note">RDF is agnostic about what the IRI stands for. However,
+    <p class="note">RDF is agnostic about what the IRI stands for. However,
     IRIs may be given meaning by particular vocabularies or
-    conventions. VIAF (see example above) is an example of such a vocabulary. RDF
-    vocabularies are discussed in more detail in Sec. <a
-    href="#section-vocabulary">"RDF vocabularies"</a>. </p-->
+    conventions. RDF vocabularies are discussed in more detail in Sec.
+    <a href="#section-vocabulary">"RDF vocabularies"</a>. </p>
     
     </section>
 
@@ -497,12 +496,12 @@
     multiple graphs that is closely aligned with SPARQL. </p> 
 
     <figure>
-      <img src="example-multiple-graphs.jpg" width="60%"
+      <img src="example-multiple-graphs.jpg" width="75%"
                 alt="Informal graph of the multiple graphs example">
       <figcaption>Informal graph of the multiple graphs example</figcaption>
     </figure>
 
-    <p class="issue">Todo: include figure</p>
+    <p class="issue">Todo: update figure</p>
 
     </section>
 
@@ -861,6 +860,8 @@
       <figcaption>Triples resulting from the TriG example. @@ todo</figcaption>
     </figure>
 
+    <p class="issue">Todo: include figure</p>
+
     </section>
 
     <section id="subsection-other-syntaxes">
@@ -1000,7 +1001,9 @@
 
     <h2>RDF Data</h2>
 
-    <p>A large amount of RDF data is available as part of the Linked
+    <p>RDF allows you to combine triples from any source into a graph
+    and process it as legal RDF. A large amount of RDF data is
+    available as part of the Linked 
     Data [[LINKED-DATA]] cloud. Datasets are being published and
     interlinked on the Web using RDF, and many of them offer a
     querying facility through SPARQL [[!SPARQL11-OVERVIEW]]. Examples
@@ -1026,8 +1029,25 @@
     <p>A list of datasets available within the Linked Data cloud is maintained at
     <a href="http://datahub.io/organization/lodcloud">datahub.io</a>.</p>
 
+    <P>A number of vocabulary terms have become popular for
+    recording links between RDF data sources. A popular example is the
+    <code>sameAs</code> property provided by the OWL vocabulary. This
+    property can be used to indicate that two IRIs point in fact 
+    to the same resource. This is useful because different publishers
+    may use different identifiers to denote the same thing. For
+    example, VIAF (see above) also has an IRI denoting Leonardo da
+    Vinci. With the help of <code>owl:sameAs</code> we can record this
+    information:</p>
+
+    <pre class="example">
+    &lt;http://dbpedia.org/resource/Leonardo_da_Vinci&gt;
+        owl:sameAs &lt;http://viaf.org/viaf/24604287/&gt; .
+    </pre>
+
+    <p>Such links can be deployed by RDF data-processing
+    software. </p>
     
-</section>
+    </section>
 
 <section id="section-other-syntaxes" class="appendix">