diff --git a/Form/DataTransformer/EntitiesToPropertyTransformer.php b/Form/DataTransformer/EntitiesToPropertyTransformer.php
index d6a9fd8..ad24962 100644
--- a/Form/DataTransformer/EntitiesToPropertyTransformer.php
+++ b/Form/DataTransformer/EntitiesToPropertyTransformer.php
@@ -55,7 +55,7 @@ public function __construct(ObjectManager $em, $class, $textProperty = null, $pr
      * @param mixed $entities
      * @return array
      */
-    public function transform($entities)
+    public function transform(mixed $entities): mixed
     {
         if (empty($entities)) {
             return array();
@@ -87,7 +87,7 @@ public function transform($entities)
      * @param array $values
      * @return array
      */
-    public function reverseTransform($values)
+    public function reverseTransform(mixed $values): mixed
     {
         if (!is_array($values) || empty($values)) {
             return array();
diff --git a/Form/DataTransformer/EntityToPropertyTransformer.php b/Form/DataTransformer/EntityToPropertyTransformer.php
index 72a30a9..2b7bb16 100644
--- a/Form/DataTransformer/EntityToPropertyTransformer.php
+++ b/Form/DataTransformer/EntityToPropertyTransformer.php
@@ -56,7 +56,7 @@ public function __construct(ObjectManager $em, $class, $textProperty = null, $pr
      * @param mixed $entity
      * @return array
      */
-    public function transform($entity)
+    public function transform(mixed $entity): mixed
     {
         $data = array();
         if (empty($entity)) {
@@ -85,7 +85,7 @@ public function transform($entity)
      * @param string $value
      * @return mixed|null|object
      */
-    public function reverseTransform($value)
+    public function reverseTransform(mixed $value): mixed
     {
         if (empty($value)) {
             return null;