diff --git a/django_mailbox/models.py b/django_mailbox/models.py
index 2d9eeff..e36bf00 100644
--- a/django_mailbox/models.py
+++ b/django_mailbox/models.py
@@ -75,7 +75,7 @@ ATTACHMENT_INTERPOLATION_HEADER = getattr(
 
 class ActiveMailboxManager(models.Manager):
     def get_queryset(self):
-        return super(ActiveMailboxManager, self).get_query_set().filter(
+        return super(ActiveMailboxManager, self).get_queryset().filter(
             active=True,
         )
 
@@ -352,21 +352,21 @@ class Mailbox(models.Model):
 
 class IncomingMessageManager(models.Manager):
     def get_queryset(self):
-        return super(IncomingMessageManager, self).get_query_set().filter(
+        return super(IncomingMessageManager, self).get_queryset().filter(
             outgoing=False,
         )
 
 
 class OutgoingMessageManager(models.Manager):
     def get_queryset(self):
-        return super(OutgoingMessageManager, self).get_query_set().filter(
+        return super(OutgoingMessageManager, self).get_queryset().filter(
             outgoing=True,
         )
 
 
 class UnreadMessageManager(models.Manager):
     def get_queryset(self):
-        return super(UnreadMessageManager, self).get_query_set().filter(
+        return super(UnreadMessageManager, self).get_queryset().filter(
             read=None
         )