try:
             changes = [
                 p.change for p in
-                self.sitechunkpublish_set.order_by('change__chunk__number')
+                self.sitechunkpublish_set.order_by('change__tree__number')
             ]
 
-            self.site.publish(self, changes=changes)
+            self.site_book.site.publish(self, changes=changes)
 
         except Exception:
             self.status = 110