diff --git a/xsl/annotation.xsl b/xsl/annotation.xsl
index d1cf6c5..92c1a67 100644
--- a/xsl/annotation.xsl
+++ b/xsl/annotation.xsl
@@ -8,7 +8,7 @@
   <xsl:key name="libraries" match="library" use="@name"/>
   <xsl:key name="macros" match="macro" use="@name"/>
   <xsl:key name="headers" match="header" use="@name"/>
-  <xsl:key name="named-entities" match="class|struct|union|function|overloaded-function|macro|library|*[attribute::id]" use="@name|@id"/>
+  <xsl:key name="named-entities" match="class|struct|union|function|overloaded-function|macro|library|namespace/data-member|header/data-member|*[attribute::id]" use="@name|@id"/>
 
   <xsl:template match="function|overloaded-function" mode="generate.id">
     <xsl:variable name="name" select="normalize-space(@name)"/>