diff --git a/doc/common/section_keystone-external-auth.xml b/doc/common/section_keystone-external-auth.xml
index d663ac0e0f..8d30367426 100644
--- a/doc/common/section_keystone-external-auth.xml
+++ b/doc/common/section_keystone-external-auth.xml
@@ -10,7 +10,7 @@
         can use external authentication methods that differ from the
         authentication provided by the identity store back end. For
         example, you can use an SQL identity back end together with
-        X.509 authentication, Kerberos, and so on instead of using the
+        X.509 authentication and Kerberos, instead of using the
         user name and password combination.</para>
     <section xml:id="keystone-httpd-auth">
         <title>Use HTTPD authentication</title>