diff --git a/src/Url.php b/src/Url.php
index eff949a..c50954a 100644
--- a/src/Url.php
+++ b/src/Url.php
@@ -538,12 +538,17 @@ class Url {
    *
    * @param string $url The URL
    * @param string $parameter The parameter name
-   * @param string|null $value The parameter value (optional)
+   * @param string|array<string>|null $value The parameter value (optional)
    * @param boolean $encode Set if parameter value must be URL encoded (optional, default: true)
    *
    * @return string The completed URL
    */
   public static function add_url_parameter($url, $parameter, $value=null, $encode=true) {
+    if (is_array($value)) {
+      foreach($value as $v)
+        $url = self :: add_url_parameter($url, $parameter."[]", $v);
+      return $url;
+    }
     if (strpos($url, '?') === false)
       $url .= '?';
     else