diff --git a/lib/create-clusters.js b/lib/create-clusters.js
index ee6b61f4..34522d43 100644
--- a/lib/create-clusters.js
+++ b/lib/create-clusters.js
@@ -1,4 +1,5 @@
 var util = require("./util"),
+    d3 = require("./d3"),
     addLabel = require("./label/add-label");
 
 module.exports = createClusters;