added link to upgrading guide
diff --git a/user_guide/installation/upgrading.html b/user_guide/installation/upgrading.html
index ecc00b2..fb931bb 100644
--- a/user_guide/installation/upgrading.html
+++ b/user_guide/installation/upgrading.html
@@ -60,6 +60,7 @@
<p>Please read the upgrade notes corresponding to the version you are upgrading from.</p>
<ul>
+<li><a href="upgrade_160.html">Upgrading from 1.5.4 to 1.6.0</a></li>
<li><a href="upgrade_154.html">Upgrading from 1.5.3 to 1.5.4</a></li>
<li><a href="upgrade_153.html">Upgrading from 1.5.2 to 1.5.3</a></li>
<li><a href="upgrade_152.html">Upgrading from 1.5.0 or 1.5.1 to 1.5.2</a></li>