diff --git a/help/C/zenity-C.omf b/help/C/zenity-C.omf
index 8b9e577..ecc2882 100644
--- a/help/C/zenity-C.omf
+++ b/help/C/zenity-C.omf
@@ -32,6 +32,7 @@
      <format mime="text/xml" dtd="-//OASIS//DTD DocBook XML V4.1.2//EN"/>
      <identifier url="zenity.xml"/>
      <language code="C"/>
+     <relation seriesid="1e4f989c-287a-11d7-84e2-b1f3b939ba73"/>
      <rights type="GNU FDL" license.version="1.1" holder="Sun Microsystems"/>
   </resource>
 </omf>