diff --git a/doc/src/sgml/installation.sgml b/doc/src/sgml/installation.sgml
new file mode 100644
index c02ed87..2457fc5
*** a/doc/src/sgml/installation.sgml
--- b/doc/src/sgml/installation.sgml
*************** su - postgres
*** 280,285 ****
--- 280,293 ----
        encryption using those services.
       </para>
      </listitem>
+ 
+     <listitem>
+      <para>
+       To build the <productname>PostgreSQL</productname> documentation, 
+       there is a separate set of requirements.
+       See <xref linkend="docguide-toolsets">.
+      </para>
+     </listitem>
     </itemizedlist>
    </para>