diff --git a/Resources/doc/index.md b/Resources/doc/index.md
index a009399..ef1f4d4 100644
--- a/Resources/doc/index.md
+++ b/Resources/doc/index.md
@@ -87,9 +87,9 @@ mobile_detect:
     cookie_key: "device_view"                     # default
     cookie_expire_datetime_modifier: "+1 month"   # default
     switch_param: "device_view"                   # default
-    device_view_class: "SunCat\MobileDetectBundle\Helper\DeviceView"
-    request_response_listener_class: "SunCat\MobileDetectBundle\EventListener\RequestResponseListener"
-    twig_extension_class: "SunCat\MobileDetectBundle\Twig\Extension\MobileDetectExtension"
+    device_view_class: 'SunCat\MobileDetectBundle\Helper\DeviceView'
+    request_response_listener_class: 'SunCat\MobileDetectBundle\EventListener\RequestResponseListener'
+    twig_extension_class: 'SunCat\MobileDetectBundle\Twig\Extension\MobileDetectExtension'
 ```
 
 You can also create route specific rules for redirecting in your routing.yml.