diff --git a/Models/EditorDoc.php b/Models/EditorDoc.php
index 4232a9f..dab6417 100755
--- a/Models/EditorDoc.php
+++ b/Models/EditorDoc.php
@@ -261,7 +261,7 @@ class EditorDoc implements \JsonSerializable, ArrayableInterface
     /**
      * {@inheritdoc}
      */
-    public function jsonSerialize()
+    public function jsonSerialize() : mixed
     {
         return $this->toArray();
     }
diff --git a/Models/EditorDocHistory.php b/Models/EditorDocHistory.php
index bd7a5fb..a8bd9da 100644
--- a/Models/EditorDocHistory.php
+++ b/Models/EditorDocHistory.php
@@ -156,7 +156,7 @@ class EditorDocHistory implements \JsonSerializable, ArrayableInterface
     /**
      * {@inheritdoc}
      */
-    public function jsonSerialize()
+    public function jsonSerialize() : mixed
     {
         return $this->toArray();
     }
diff --git a/Models/EditorDocType.php b/Models/EditorDocType.php
index a6345e1..ba4723f 100644
--- a/Models/EditorDocType.php
+++ b/Models/EditorDocType.php
@@ -125,7 +125,7 @@ class EditorDocType implements \JsonSerializable, ArrayableInterface
     /**
      * {@inheritdoc}
      */
-    public function jsonSerialize()
+    public function jsonSerialize() : mixed
     {
         return $this->toArray();
     }
diff --git a/Models/EditorDocTypeL11n.php b/Models/EditorDocTypeL11n.php
index 10a2fb7..7eb3966 100644
--- a/Models/EditorDocTypeL11n.php
+++ b/Models/EditorDocTypeL11n.php
@@ -126,7 +126,7 @@ class EditorDocTypeL11n implements \JsonSerializable, ArrayableInterface
     /**
      * {@inheritdoc}
      */
-    public function jsonSerialize()
+    public function jsonSerialize() : mixed
     {
         return $this->toArray();
     }