diff --git a/converter.py b/converter.py
index daaf56d1573639a68b5503cf22503b14831d8d22..d705b46e7cdd1fd66ce22bd72e88658f1879ff7e 100644
--- a/converter.py
+++ b/converter.py
@@ -105,6 +105,10 @@ class TestConverter(unittest.TestCase):
         res = self.c.convert(0)
         self.assertEqual(res, 'Es gibt keine römische Null')
 
+    def test_convertFourty(self):
+        res = self.c.convert(40)
+        self.assertEqual(res, 'XL')
+