diff --git a/src/ol/structs/priorityqueue.js b/src/ol/structs/priorityqueue.js
index 8ecc516ae9..d5ec23b58e 100644
--- a/src/ol/structs/priorityqueue.js
+++ b/src/ol/structs/priorityqueue.js
@@ -1,5 +1,6 @@
 goog.provide('ol.structs.PriorityQueue');
 
+goog.require('ol');
 goog.require('ol.asserts');
 goog.require('ol.obj');