diff --git a/html/labels.html b/html/labels.html
index ffb39cd66b40ba02ad4b3f1bea9b7649fdf2f16b..5417f79614cad5c9c2a093f235911ca5a0c5a802 100644
--- a/html/labels.html
+++ b/html/labels.html
@@ -47,7 +47,11 @@
 <dt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#id</dd>
 <dd>URI identifying the alignment.</dd>
 <dt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#method</dd>
-<dd>CLASSNAME of the generating matching method.</dd>
+<dd>CLASSNAME of the generating matching method (or operation).</dd>
+<dt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#relation</dd>
+<dd>URI identifying the classname implementing the relation structure.</dd>
+<dt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#confidence</dd>
+<dd>URI identifying the classname implementing the confidence structure.</dd>
 <dt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#derivedFrom</dd>
 <dd>URI the alignment from which this one is issued, if applicable</dd>
 <dt>http://knowledgeweb.semanticweb.org/heterogeneity/alignment#parameters</dd>