diff --git a/externs/olx.js b/externs/olx.js
index a722852e4a..2e8b833ede 100644
--- a/externs/olx.js
+++ b/externs/olx.js
@@ -6523,6 +6523,13 @@ olx.ViewState;
 olx.ViewState.prototype.center;
 
 
+/**
+ * @type {ol.proj.Projection}
+ * @api
+ */
+olx.ViewState.prototype.projection;
+
+
 /**
  * @type {number}
  * @api