diff --git a/lib/roar/rails/formats.rb b/lib/roar/rails/formats.rb
index bfd08a4..b8b3401 100644
--- a/lib/roar/rails/formats.rb
+++ b/lib/roar/rails/formats.rb
@@ -42,7 +42,7 @@ def collection_representer(format, model, controller_path)
     end
 
     def entity_representer(format, model, controller_path)
-      model_name = model.class.name.underscore
+      model_name = model.model_name.name.underscore
 
       if namespace = controller_path.namespace
         model_name = "#{namespace}/#{model_name}"
@@ -71,4 +71,4 @@ def namespace
       end
     end
   end
-end
\ No newline at end of file
+end