diff --git a/demos/simple/simple.html b/demos/simple/simple.html
index 9e72a4d..251935f 100644
--- a/demos/simple/simple.html
+++ b/demos/simple/simple.html
@@ -30,6 +30,7 @@
 </div>
 <script type="text/javascript" src="../../resources/interface.js"></script>
 <script type="text/javascript" src="../../resources/map_data.js"></script>
+<script type="text/javascript" src="../../resources/units_data.js"></script>
 <script type="text/javascript" src="../../dist/agentmaps.js"></script>
 <script type="text/javascript" src="simple.js"></script>
 <script>