diff --git a/cpp/LinearFactorGraph.h b/cpp/LinearFactorGraph.h
index 36aed3251..cf3e35ee5 100644
--- a/cpp/LinearFactorGraph.h
+++ b/cpp/LinearFactorGraph.h
@@ -17,11 +17,10 @@
 #include "LinearFactor.h"
 #include "VectorConfig.h"
 #include "FactorGraph.h"
+#include "ChordalBayesNet.h"
 
 namespace gtsam {
 
-	class ChordalBayesNet;
-
   /**
    * A Linear Factor Graph is a factor graph where all factors are Gaussian, i.e.
    *   Factor == LinearFactor