diff --git a/reference/spl/splobjectstorage/attach.xml b/reference/spl/splobjectstorage/attach.xml
index 83ca9883cc1e..ee940f37a7d3 100644
--- a/reference/spl/splobjectstorage/attach.xml
+++ b/reference/spl/splobjectstorage/attach.xml
@@ -21,6 +21,10 @@
   <para>
    Adds an <type>object</type> inside the storage, and optionally associate it to some data.
   </para>
+  <simpara>
+   This method is an alias of <methodname>SplObjectStorage::offsetSet</methodname>.
+  </simpara>
+
  </refsect1>
 
  <refsect1 role="parameters">