diff --git a/gtsam_unstable/nonlinear/ExpressionFactorGraph.h b/gtsam_unstable/nonlinear/ExpressionFactorGraph.h
new file mode 100644
index 000000000..0edac858d
--- /dev/null
+++ b/gtsam_unstable/nonlinear/ExpressionFactorGraph.h
@@ -0,0 +1,51 @@
+/* ----------------------------------------------------------------------------
+
+ * GTSAM Copyright 2010, Georgia Tech Research Corporation, 
+ * Atlanta, Georgia 30332-0415
+ * All Rights Reserved
+ * Authors: Frank Dellaert, et al. (see THANKS for the full author list)
+
+ * See LICENSE for the license information
+
+ * -------------------------------------------------------------------------- */
+
+/**
+ *  @file  ExpressionFactorGraph.h
+ *  @brief Factor graph that supports adding ExpressionFactors directly
+ *  @author Frank Dellaert
+ *  @date December 2014
+ */
+
+#pragma once
+
+#include <gtsam_unstable/nonlinear/ExpressionFactor.h>
+#include <gtsam/nonlinear/NonlinearFactorGraph.h>
+
+namespace gtsam {
+
+/**
+ * Factor graph that supports adding ExpressionFactors directly
+ */
+class ExpressionFactorGraph: public NonlinearFactorGraph {
+
+public:
+
+  /// @name Adding Factors
+  /// @{
+
+  /**
+   * Directly add ExpressionFactor that implements |h(x)-z|^2_R
+   * @param h expression that implements measurement function
+   * @param z measurement
+   * @param R model
+   */
+  template<typename T>
+  void addExpressionFactor(const Expression<T>& h, const T& z,
+      const SharedNoiseModel& R) {
+    push_back(boost::make_shared<ExpressionFactor<T> >(R, z, h));
+  }
+
+  /// @}
+};
+
+}
diff --git a/gtsam_unstable/slam/tests/testTOAFactor.cpp b/gtsam_unstable/slam/tests/testTOAFactor.cpp
index 0565cbcbd..fd1c7a20d 100644
--- a/gtsam_unstable/slam/tests/testTOAFactor.cpp
+++ b/gtsam_unstable/slam/tests/testTOAFactor.cpp
@@ -17,10 +17,9 @@
  *  @date December 2014
  */
 
+#include <gtsam_unstable/nonlinear/ExpressionFactorGraph.h>
 #include <gtsam_unstable/geometry/Event.h>
-#include <gtsam_unstable/nonlinear/ExpressionFactor.h>
 #include <gtsam/nonlinear/LevenbergMarquardtOptimizer.h>
-#include <gtsam/nonlinear/NonlinearFactorGraph.h>
 #include <gtsam/base/numericalDerivative.h>
 
 #include <CppUnitLite/TestHarness.h>
@@ -50,31 +49,6 @@ static const double timeOfEvent = 25;
 static const Event exampleEvent(timeOfEvent, 1, 0, 0);
 static const Point3 microphoneAt0;
 
-/**
- * Factor graph that supports adding Expression Factors directly
- */
-class ExpressionFactorGraph: public NonlinearFactorGraph {
-
-public:
-
-  /// @name Adding Factors
-  /// @{
-
-  /**
-   * Directly add ExpressionFactor that implements |h(x)-z|^2_R
-   * @param h expression that implements measurement function
-   * @param z measurement
-   * @param R model
-   */
-  template<typename T>
-  void addExpressionFactor(const Expression<T>& h, const T& z,
-      const SharedNoiseModel& R) {
-    push_back(boost::make_shared<ExpressionFactor<T> >(R, z, h));
-  }
-
-  /// @}
-};
-
 //*****************************************************************************
 TEST( TOAFactor, NewWay ) {
   Key key = 12;