diff --git a/photologue_custom/models.py b/photologue_custom/models.py
index 76d7f86..76be399 100644
--- a/photologue_custom/models.py
+++ b/photologue_custom/models.py
@@ -10,7 +10,7 @@ class GalleryExtended(models.Model):
     gallery = models.OneToOneField(
         Gallery,
         related_name='extended',
-        on_delete='cascade',
+        on_delete=models.CASCADE,
     )
 
     # Add tags
@@ -41,7 +41,7 @@ class PhotoExtended(models.Model):
     photo = models.OneToOneField(
         Photo,
         related_name='extented',
-        on_delete='cascade'
+        on_delete=models.CASCADE,
     )
 
     # Add a owner field to PhotoExtended