diff --git a/IPython/nbconvert/transformers/__init__.py b/IPython/nbconvert/transformers/__init__.py
index 375b125..f944831 100755
--- a/IPython/nbconvert/transformers/__init__.py
+++ b/IPython/nbconvert/transformers/__init__.py
@@ -6,6 +6,7 @@ from .extractfigure import ExtractFigureTransformer
 from .revealhelp import RevealHelpTransformer
 from .latex import LatexTransformer
 from .sphinx import SphinxTransformer
+from .csshtmlheader import CSSHTMLHeaderTransformer
 
 # decorated function Transformers
 from .coalescestreams import coalesce_streams