diff --git a/application/src/Entity/AbstractSource.php b/application/src/Entity/AbstractSource.php
index c417aba..3a06fc4 100644
--- a/application/src/Entity/AbstractSource.php
+++ b/application/src/Entity/AbstractSource.php
@@ -7,6 +7,7 @@ use App\Entity\attribut\NodeAttribut;
 /**
  *
  * @author kevinfrantz
+ * @see https://www.doctrine-project.org/projects/doctrine-orm/en/2.6/reference/inheritance-mapping.html
  *        
  */
 abstract class AbstractSource implements SourceInterface
diff --git a/application/src/Entity/attribut/IdAttribut.php b/application/src/Entity/Attribut/IdAttribut.php
similarity index 92%
rename from application/src/Entity/attribut/IdAttribut.php
rename to application/src/Entity/Attribut/IdAttribut.php
index c4af5ca..2e31319 100644
--- a/application/src/Entity/attribut/IdAttribut.php
+++ b/application/src/Entity/Attribut/IdAttribut.php
@@ -1,5 +1,5 @@
 <?php
-namespace App\Entity\attribut;
+namespace App\Entity\Attribut;
 
 /**
  *
diff --git a/application/src/Entity/attribut/IdAttributInterface.php b/application/src/Entity/Attribut/IdAttributInterface.php
similarity index 84%
rename from application/src/Entity/attribut/IdAttributInterface.php
rename to application/src/Entity/Attribut/IdAttributInterface.php
index 93beeb1..7d1a271 100644
--- a/application/src/Entity/attribut/IdAttributInterface.php
+++ b/application/src/Entity/Attribut/IdAttributInterface.php
@@ -1,5 +1,5 @@
 <?php
-namespace App\Entity\attribut;
+namespace App\Entity\Attribut;
 
 /**
  *
diff --git a/application/src/Entity/attribut/NodeAttribut.php b/application/src/Entity/Attribut/NodeAttribut.php
similarity index 73%
rename from application/src/Entity/attribut/NodeAttribut.php
rename to application/src/Entity/Attribut/NodeAttribut.php
index f59c507..e38106f 100644
--- a/application/src/Entity/attribut/NodeAttribut.php
+++ b/application/src/Entity/Attribut/NodeAttribut.php
@@ -1,5 +1,5 @@
 <?php
-namespace App\Entity\attribut;
+namespace App\Entity\Attribut;
 
 use App\Entity\NodeInterface;
 
@@ -11,6 +11,8 @@ use App\Entity\NodeInterface;
 trait NodeAttribut{
     /**
      * @var NodeInterface
+     * @OneToOne(targetEntity="Node")
+     * @JoinColumn(name="source", referencedColumnName="id")
      */
     protected $node;
     
diff --git a/application/src/Entity/attribut/NodeAttributInterface.php b/application/src/Entity/Attribut/NodeAttributInterface.php
similarity index 87%
rename from application/src/Entity/attribut/NodeAttributInterface.php
rename to application/src/Entity/Attribut/NodeAttributInterface.php
index cfa1731..6f40f66 100644
--- a/application/src/Entity/attribut/NodeAttributInterface.php
+++ b/application/src/Entity/Attribut/NodeAttributInterface.php
@@ -1,5 +1,5 @@
 <?php
-namespace App\Entity\attribut;
+namespace App\Entity\Attribut;
 
 use App\Entity\NodeInterface;
 
diff --git a/application/src/Entity/Attribut/ParentAttribut.php b/application/src/Entity/Attribut/ParentAttribut.php
new file mode 100644
index 0000000..5a1275b
--- /dev/null
+++ b/application/src/Entity/Attribut/ParentAttribut.php
@@ -0,0 +1,29 @@
+<?php
+namespace Entity\Attribut;
+
+use Doctrine\Common\Collections\ArrayCollection;
+use App\Entity\NodeInterface;
+
+/**
+ *
+ * @author kevinfrantz
+ *        
+ */
+trait ParentAttribut {
+    /**
+     *
+     * @var ArrayCollection|NodeInterface[]
+     */
+    protected $parents;
+    
+    public function getParents(): ArrayCollection
+    {
+        return $this->parents;
+    }
+    
+    public function setParents(ArrayCollection $parents): void
+    {
+        $this->parents = $parents;
+    }
+}
+
diff --git a/application/src/Entity/Attribut/ParentsAttributInterface.php b/application/src/Entity/Attribut/ParentsAttributInterface.php
new file mode 100644
index 0000000..59dfdc9
--- /dev/null
+++ b/application/src/Entity/Attribut/ParentsAttributInterface.php
@@ -0,0 +1,17 @@
+<?php
+namespace App\Entity\Attribut;
+
+use Doctrine\Common\Collections\ArrayCollection;
+
+/**
+ *
+ * @author kevinfrantz
+ *        
+ */
+interface ParentsAttributInterface
+{
+    public function setParents(ArrayCollection $parents):void;
+    
+    public function getParents():ArrayCollection;
+}
+
diff --git a/application/src/Entity/attribut/SourceAttribut.php b/application/src/Entity/Attribut/SourceAttribut.php
similarity index 92%
rename from application/src/Entity/attribut/SourceAttribut.php
rename to application/src/Entity/Attribut/SourceAttribut.php
index 2881f99..8642ee4 100644
--- a/application/src/Entity/attribut/SourceAttribut.php
+++ b/application/src/Entity/Attribut/SourceAttribut.php
@@ -1,5 +1,5 @@
 <?php
-namespace App\Entity\attribut;
+namespace App\Entity\Attribut;
 
 use App\Entity\SourceInterface;
 
diff --git a/application/src/Entity/attribut/SourceAttributInterface.php b/application/src/Entity/Attribut/SourceAttributInterface.php
similarity index 88%
rename from application/src/Entity/attribut/SourceAttributInterface.php
rename to application/src/Entity/Attribut/SourceAttributInterface.php
index 25a6eca..3a3e808 100644
--- a/application/src/Entity/attribut/SourceAttributInterface.php
+++ b/application/src/Entity/Attribut/SourceAttributInterface.php
@@ -1,5 +1,5 @@
 <?php
-namespace App\Entity\attribut;
+namespace App\Entity\Attribut;
 
 use App\Entity\SourceInterface;
 
diff --git a/application/src/Entity/ConfigurationInterface.php b/application/src/Entity/ConfigurationInterface.php
index e7ab06a..53f175e 100644
--- a/application/src/Entity/ConfigurationInterface.php
+++ b/application/src/Entity/ConfigurationInterface.php
@@ -2,7 +2,7 @@
 namespace App\Entity;
 
 /**
- *
+ * This class is not a source!
  * @author kevinfrantz
  *        
  */
diff --git a/application/src/Entity/Node.php b/application/src/Entity/Node.php
index 3642c94..75d3d22 100644
--- a/application/src/Entity/Node.php
+++ b/application/src/Entity/Node.php
@@ -2,6 +2,9 @@
 namespace App\Entity;
 
 use Doctrine\Common\Collections\ArrayCollection;
+use App\Entity\attribut\IdAttribut;
+use App\Entity\attribut\SourceAttribut;
+use Entity\attribut\ParentAttribut;
 
 /**
  *
@@ -10,50 +13,18 @@ use Doctrine\Common\Collections\ArrayCollection;
  */
 class Node implements NodeInterface
 {
-    /**
-     * 
-     * @var int
-     */
-    protected $id;
-    
-    /**
-     * 
-     * @var SourceInterface
-     */
-    protected $source;
-    
-    /**
-     * 
-     * @var ArrayCollection|Node[]
-     */
-    protected $parents;
+    use IdAttribut,SourceAttribut, ParentAttribut;
     
     /**
      * 
      * @var ArrayCollection|Node[]
      */
     protected $childs;
-    
-    public function getParents(): ArrayCollection
-    {}
-
-    public function setParents(ArrayCollection $parents): void
-    {}
 
     public function getChilds(): ArrayCollection
     {}
 
     public function setChilds(ArrayCollection $childs): void
     {}
-    
-    public function getId(): int
-    {}
-
-    public function setSource(SourceInterface $source):void
-    {}
-
-    public function getSource(): SourceInterface
-    {}
-
 }
 
diff --git a/application/src/Entity/NodeInterface.php b/application/src/Entity/NodeInterface.php
index 7f78c5d..e1aabf5 100644
--- a/application/src/Entity/NodeInterface.php
+++ b/application/src/Entity/NodeInterface.php
@@ -2,21 +2,17 @@
 namespace App\Entity;
 
 use Doctrine\Common\Collections\ArrayCollection;
-use App\Entity\attribut\SourceAttributInterface;
+use App\Entity\Attribut\SourceAttributInterface;
+use App\Entity\Attribut\IdAttributInterface;
+use App\Entity\Attribut\ParentsAttributInterface;
 
 /**
  *
  * @author kevinfrantz
  *        
  */
-interface NodeInterface extends SourceAttributInterface
-{
-    public function getId():int;
-    
-    public function setParents(ArrayCollection $parents):void;
-    
-    public function getParents():ArrayCollection;
-    
+interface NodeInterface extends SourceAttributInterface, IdAttributInterface,ParentsAttributInterface
+{   
     public function setChilds(ArrayCollection $childs):void;
     
     public function getChilds():ArrayCollection;
diff --git a/application/src/Entity/Property.php b/application/src/Entity/Property.php
index b024f12..69db1a9 100644
--- a/application/src/Entity/Property.php
+++ b/application/src/Entity/Property.php
@@ -8,7 +8,7 @@ use Doctrine\Common\Collections\ArrayCollection;
  * @author kevinfrantz
  *        
  */
-class Property extends AbstractSource implements PropertyInterface
+class Property implements PropertyInterface
 {
     /**
      *