diff --git a/documentation/ref-manual/ref-classes.xml b/documentation/ref-manual/ref-classes.xml
index c86875ed84..8184c1c5a9 100644
--- a/documentation/ref-manual/ref-classes.xml
+++ b/documentation/ref-manual/ref-classes.xml
@@ -660,6 +660,34 @@
     </para>
 </section>
 
+<section id='ref-classes-distutils3'>
+    <title><filename>distutils3.bbclass</filename></title>
+
+    <para>
+        The <filename>distutils3</filename> class supports recipes for Python
+        version 3.x extensions, which are simple.
+        These recipes usually only need to point to the source's archive and
+        then inherit the proper class.
+        Building is split into two methods depending on which method the
+        module authors used.
+        <itemizedlist>
+            <listitem><para>Extensions that use an Autotools-based build system
+                require Autotools and
+                <filename>distutils</filename>-based classes in their recipes.
+                </para></listitem>
+            <listitem><para>Extensions that use
+                <filename>distutils</filename>-based build systems require
+                the <filename>distutils</filename> class in their recipes.
+                </para></listitem>
+            <listitem><para>Extensions that use the setuptools3-based build
+                systems require the
+                <link linkend='ref-classes-setuptools'><filename>setuptools3</filename></link>
+                class in their recipes.
+                </para></listitem>
+        </itemizedlist>
+    </para>
+</section>
+
 <section id='ref-classes-externalsrc'>
     <title><filename>externalsrc.bbclass</filename></title>