Docs

docs/I18n/I18n.md

@@ -61,6 +61,7 @@ if (!$language) {
 	$language = $this->request->getParam('language');
 }
 ```
+(before CakePHP 3.4+ it would be `param()`)
 
 And make sure your routes are all adjusted to accept and parse the language param:
 ```php