diff --git a/Models/Department.php b/Models/Department.php
index 3c8f88c..157be34 100644
--- a/Models/Department.php
+++ b/Models/Department.php
@@ -104,7 +104,7 @@ class Department
      */
     public function __toString()
     {
-        return $this->jsonSerialize();
+        return json_encode($this->toArray());
     }
 
     /**
@@ -117,6 +117,6 @@ class Department
      */
     public function jsonSerialize()
     {
-        return json_encode($this->toArray());
+        return $this->toArray();
     }
 }
diff --git a/Models/Position.php b/Models/Position.php
index 2b66201..2de467d 100644
--- a/Models/Position.php
+++ b/Models/Position.php
@@ -93,7 +93,7 @@ class Position implements ArrayableInterface, \JsonSerializable
      */
     public function __toString()
     {
-        return $this->jsonSerialize();
+        return json_encode($this->toArray());
     }
 
     /**
@@ -106,6 +106,6 @@ class Position implements ArrayableInterface, \JsonSerializable
      */
     public function jsonSerialize()
     {
-        return json_encode($this->toArray());
+        return $this->toArray();
     }
 }
diff --git a/Models/Unit.php b/Models/Unit.php
index 4f14a26..2729f44 100644
--- a/Models/Unit.php
+++ b/Models/Unit.php
@@ -93,7 +93,7 @@ class Unit implements ArrayableInterface, \JsonSerializable
      */
     public function __toString()
     {
-        return $this->jsonSerialize();
+        return json_encode($this->toArray());
     }
 
     /**
@@ -106,6 +106,6 @@ class Unit implements ArrayableInterface, \JsonSerializable
      */
     public function jsonSerialize()
     {
-        return json_encode($this->toArray());
+        return $this->toArray();
     }
 }