diff --git a/db/migrations/2018_10_01_000000_create_users_tables.php b/db/migrations/2018_10_01_000000_create_users_tables.php
index 55ee382e..d6778c52 100644
--- a/db/migrations/2018_10_01_000000_create_users_tables.php
+++ b/db/migrations/2018_10_01_000000_create_users_tables.php
@@ -16,6 +16,7 @@ use stdClass;
 class CreateUsersTables extends Migration
 {
     use ChangesReferences;
+    use Reference;
 
     /**
      * Run the migration
@@ -273,17 +274,4 @@ class CreateUsersTables extends Migration
 
         $this->schema->drop('users');
     }
-
-    /**
-     * @param Blueprint $table
-     */
-    protected function referencesUser(Blueprint $table)
-    {
-        $table->unsignedInteger('user_id');
-
-        $table->primary('user_id');
-        $table->foreign('user_id')
-            ->references('id')->on('users')
-            ->onDelete('cascade');
-    }
 }
diff --git a/db/migrations/Reference.php b/db/migrations/Reference.php
new file mode 100644
index 00000000..4c35b59b
--- /dev/null
+++ b/db/migrations/Reference.php
@@ -0,0 +1,36 @@
+<?php
+
+namespace Engelsystem\Migrations;
+
+use Illuminate\Database\Schema\Blueprint;
+
+trait Reference
+{
+    /**
+     * @param Blueprint $table
+     * @param bool      $setPrimary
+     */
+    protected function referencesUser(Blueprint $table, $setPrimary = true)
+    {
+        $this->references($table, 'users', 'user_id', $setPrimary);
+    }
+
+    /**
+     * @param Blueprint $table
+     * @param string    $targetTable
+     * @param string    $fromColumn
+     * @param bool      $setPrimary
+     */
+    protected function references(Blueprint $table, $targetTable, $fromColumn, $setPrimary = false)
+    {
+        $table->unsignedInteger($fromColumn);
+
+        if ($setPrimary) {
+            $table->primary($fromColumn);
+        }
+
+        $table->foreign($fromColumn)
+            ->references('id')->on($targetTable)
+            ->onDelete('cascade');
+    }
+}