diff --git a/IPython/nbformat/reader.py b/IPython/nbformat/reader.py
index 54ec896..78e8a1d 100644
--- a/IPython/nbformat/reader.py
+++ b/IPython/nbformat/reader.py
@@ -18,9 +18,9 @@ Authors:
 
 import json
 
-import v1
-import v2
-import v3
+from . import v1
+from . import v2
+from . import v3
 
 versions = {
     1: v1,