diff --git a/src/ol/style/stroke.js b/src/ol/style/stroke.js
index 5d11b69fc3..7a6b6b8f6f 100644
--- a/src/ol/style/stroke.js
+++ b/src/ol/style/stroke.js
@@ -1,5 +1,7 @@
 goog.provide('ol.style.Stroke');
 
+goog.require('ol');
+
 
 /**
  * @classdesc