diff --git a/examples/wms.js b/examples/wms.js
index 7f53e21c07..f68fcae9ac 100644
--- a/examples/wms.js
+++ b/examples/wms.js
@@ -21,13 +21,15 @@ var layers = new ol.Collection([
   new ol.layer.TileLayer({
     source: new ol.source.TiledWMS({
       url: 'http://demo.opengeo.org/geoserver/wms',
+      crossOrigin: null,
       params: {'LAYERS': 'topp:states', 'TILED': true}
     })
   })
 ]);
 var map = new ol.Map({
-  center: new ol.Coordinate(-10997148, 4569099),
+  renderer: ol.RendererHint.DOM,
   layers: layers,
   target: 'map',
+  center: new ol.Coordinate(-10997148, 4569099),
   zoom: 4
 });
diff --git a/src/ol/source/tiledwmssource.js b/src/ol/source/tiledwmssource.js
index 8ad8e4be12..32353495a7 100644
--- a/src/ol/source/tiledwmssource.js
+++ b/src/ol/source/tiledwmssource.js
@@ -17,7 +17,7 @@ goog.require('ol.tilegrid.TileGrid');
  * @typedef {{attributions: (Array.<ol.Attribution>|undefined),
  *            params: Object,
  *            version: (string|undefined),
- *            crossOrigin: (string|undefined),
+ *            crossOrigin: (null|string|undefined),
  *            extent: (ol.Extent|undefined),
  *            tileGrid: (ol.tilegrid.TileGrid|undefined),
  *            maxZoom: (number|undefined),
diff --git a/src/ol/source/tilesource.js b/src/ol/source/tilesource.js
index bd8293f7d3..9b915efe16 100644
--- a/src/ol/source/tilesource.js
+++ b/src/ol/source/tilesource.js
@@ -14,7 +14,7 @@ goog.require('ol.tilegrid.TileGrid');
 
 /**
  * @typedef {{attributions: (Array.<ol.Attribution>|undefined),
- *            crossOrigin: (string|undefined),
+ *            crossOrigin: (null|string|undefined),
  *            extent: (ol.Extent|undefined),
  *            projection: (ol.Projection|undefined),
  *            tileGrid: (ol.tilegrid.TileGrid|undefined),