diff --git a/longs/models.py b/longs/models.py
index 6bd45655..60f87028 100644
--- a/longs/models.py
+++ b/longs/models.py
@@ -116,7 +116,7 @@ class Long(models.Model):
         return authors
 
     def __str__(self):
-        examinations = [series.get_examinations() for series in self.series]
+        examinations = [series.get_examinations() for series in self.series.all()]
         return "{} : {}".format(self.history, ", ".join(examinations))
 
     def GetExams(self):