diff --git a/examples/gpx.js b/examples/gpx.js
index f1d748dce0..02361d7f3c 100644
--- a/examples/gpx.js
+++ b/examples/gpx.js
@@ -96,7 +96,7 @@ map.on('click', function(evt) {
 
 var exportGPXElement = document.getElementById('export-gpx');
 if ('download' in exportGPXElement) {
-  var vectorSource = /** @type {ol.source.Vector} */ (vector.getSource());
+  var vectorSource = vector.getSource();
   exportGPXElement.addEventListener('click', function(e) {
     if (!exportGPXElement.href) {
       var features = [];
diff --git a/examples/kml.js b/examples/kml.js
index ca4c23ac96..b4ec38028b 100644
--- a/examples/kml.js
+++ b/examples/kml.js
@@ -63,7 +63,7 @@ map.on('click', function(evt) {
 
 var exportKMLElement = document.getElementById('export-kml');
 if ('download' in exportKMLElement) {
-  var vectorSource = /** @type {ol.source.Vector} */ (vector.getSource());
+  var vectorSource = vector.getSource();
   exportKMLElement.addEventListener('click', function(e) {
     if (!exportKMLElement.href) {
       var features = [];
diff --git a/src/ol/renderer/canvas/canvasvectorlayerrenderer.js b/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
index 4e90b9b973..e1a0ad69f2 100644
--- a/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
+++ b/src/ol/renderer/canvas/canvasvectorlayerrenderer.js
@@ -11,7 +11,6 @@ goog.require('ol.render.EventType');
 goog.require('ol.render.canvas.ReplayGroup');
 goog.require('ol.renderer.canvas.Layer');
 goog.require('ol.renderer.vector');
-goog.require('ol.source.Vector');
 
 
 
@@ -168,7 +167,6 @@ ol.renderer.canvas.VectorLayer.prototype.prepareFrame =
   var vectorLayer = /** @type {ol.layer.Vector} */ (this.getLayer());
   goog.asserts.assertInstanceof(vectorLayer, ol.layer.Vector);
   var vectorSource = vectorLayer.getSource();
-  goog.asserts.assertInstanceof(vectorSource, ol.source.Vector);
 
   this.updateAttributions(
       frameState.attributions, vectorSource.getAttributions());