diff --git a/src/ol/format/geojsonformat.js b/src/ol/format/geojsonformat.js
index c29a15b7f2..457953a03d 100644
--- a/src/ol/format/geojsonformat.js
+++ b/src/ol/format/geojsonformat.js
@@ -526,7 +526,7 @@ ol.format.GeoJSON.prototype.writeFeatureObject = function(
  *
  * @function
  * @param {Array.<ol.Feature>} features Features.
- * @param {olx.format.WriteOptions} options Write options.
+ * @param {olx.format.WriteOptions=} opt_options Write options.
  * @return {string} GeoJSON.
  * @api stable
  */