diff --git a/externs/olx.js b/externs/olx.js
index 8528a194f0..c06867e93e 100644
--- a/externs/olx.js
+++ b/externs/olx.js
@@ -1682,7 +1682,7 @@ olx.format.GeoJSONOptions;
 
 
 /**
- * Default data projection.
+ * Default data projection. Default is `EPSG:4326`.
  * @type {ol.proj.ProjectionLike}
  * @api stable
  */
@@ -1797,7 +1797,7 @@ olx.format.TopoJSONOptions;
 
 
 /**
- * Default data projection.
+ * Default data projection. Default is `EPSG:4326`.
  * @type {ol.proj.ProjectionLike}
  * @api stable
  */