diff --git a/docs/standalone.xml b/docs/standalone.xml
index 8aba62886..cfaf547aa 100644
--- a/docs/standalone.xml
+++ b/docs/standalone.xml
@@ -207,7 +207,7 @@
     <para>If you are installing Shorewall version 3.4.0 or later then as each
     file is introduced, I suggest that you look at the actual file on your
     system and that you look at the <ulink
-    url="configuration_file_basics.html#Manpages">man page</ulink> for that
+    url="configuration_file_basics.htm#Manpages">man page</ulink> for that
     file. For example, to look at the man page for the
     <filename>/etc/shorewall/zones</filename> file, type <command>man
     shorewall-zones</command> at a shell prompt.</para>
diff --git a/docs/three-interface.xml b/docs/three-interface.xml
index edb6c3a1f..2a84ea412 100644
--- a/docs/three-interface.xml
+++ b/docs/three-interface.xml
@@ -233,7 +233,7 @@
     <para>If you are installing Shorewall version 3.4.0 or later then as each
     file is introduced, I suggest that you look at the actual file on your
     system and that you look at the <ulink
-    url="configuration_file_basics.html#Manpages">man page</ulink> for that
+    url="configuration_file_basics.htm#Manpages">man page</ulink> for that
     file. For example, to look at the man page for the
     <filename>/etc/shorewall/zones</filename> file, type <command>man
     shorewall-zones</command> at a shell prompt.</para>
diff --git a/docs/two-interface.xml b/docs/two-interface.xml
index b90256b0a..50f1e1b01 100644
--- a/docs/two-interface.xml
+++ b/docs/two-interface.xml
@@ -214,7 +214,7 @@
     <para>If you are installing Shorewall version 3.4.0 or later then as each
     file is introduced, I suggest that you look at the actual file on your
     system and that you look at the <ulink
-    url="configuration_file_basics.html#Manpages">man page</ulink> for that
+    url="configuration_file_basics.htm#Manpages">man page</ulink> for that
     file. For example, to look at the man page for the
     <filename>/etc/shorewall/zones</filename> file, type <command>man
     shorewall-zones</command> at a shell prompt.</para>