diff --git a/en_US.ISO8859-1/articles/contributors/contrib.additional.xml b/en_US.ISO8859-1/articles/contributors/contrib.additional.xml
index aa9c4bc30c..72c97fbafa 100644
--- a/en_US.ISO8859-1/articles/contributors/contrib.additional.xml
+++ b/en_US.ISO8859-1/articles/contributors/contrib.additional.xml
@@ -6258,6 +6258,11 @@
       <email>marc.vanwoerkom@fernuni-hagen.de</email></para>
   </listitem>
 
+  <listitem>
+    <para>Marcel Kaiser
+      <email>mk@nic-nac-project.org</email></para>
+  </listitem>
+
   <listitem>
     <para>Marcello Silva Coutinho
       <email>marcellocoutinho@gmail.com</email></para>