diff --git a/Resources/doc/form.md b/Resources/doc/form.md
index 6b8d101..bf22d80 100644
--- a/Resources/doc/form.md
+++ b/Resources/doc/form.md
@@ -9,7 +9,7 @@ namespace Acme\DemoBundle\Form;
 
 use Symfony\Component\Form\AbstractType;
 use Symfony\Component\Form\FormBuilderInterface;
-use Symfony\Component\OptionsResolver\OptionsResolverInterface;
+use Symfony\Component\OptionsResolver\OptionsResolver;
 use Symfony\Component\Validator\Constraints as Assert;
 
 /**
@@ -44,7 +44,7 @@ class UserType extends AbstractType
     /**
      * {@inheritdoc}
      */
-    public function setDefaultOptions(OptionsResolverInterface $resolver)
+    public function setDefaultOptions(OptionsResolver $resolver)
     {
         $resolver->setDefaults([
             'data_class' => 'Acme\DemoBundle\Entity\User'