diff --git a/gtsam/nonlinear/NonlinearFactorGraph-inl.h b/gtsam/nonlinear/NonlinearFactorGraph-inl.h
index a6f2bddb3..4704b26e9 100644
--- a/gtsam/nonlinear/NonlinearFactorGraph-inl.h
+++ b/gtsam/nonlinear/NonlinearFactorGraph-inl.h
@@ -125,11 +125,11 @@ namespace gtsam {
 
 	/* ************************************************************************* */
 	template<class VALUES>
-	typename FactorGraph<GaussianFactor>::shared_ptr NonlinearFactorGraph<VALUES>::linearize(
+	typename GaussianFactorGraph::shared_ptr NonlinearFactorGraph<VALUES>::linearize(
 			const VALUES& config, const Ordering& ordering) const {
 
 		// create an empty linear FG
-		typename FactorGraph<GaussianFactor>::shared_ptr linearFG(new FactorGraph<GaussianFactor>);
+		typename GaussianFactorGraph::shared_ptr linearFG(new GaussianFactorGraph);
 		linearFG->reserve(this->size());
 
 		// linearize all factors
diff --git a/gtsam/nonlinear/NonlinearFactorGraph.h b/gtsam/nonlinear/NonlinearFactorGraph.h
index 5a13a982f..c7f10475a 100644
--- a/gtsam/nonlinear/NonlinearFactorGraph.h
+++ b/gtsam/nonlinear/NonlinearFactorGraph.h
@@ -85,7 +85,7 @@ namespace gtsam {
 		/**
 		 * linearize a nonlinear factor graph
 		 */
-		boost::shared_ptr<FactorGraph<GaussianFactor> >
+		boost::shared_ptr<GaussianFactorGraph >
 				linearize(const VALUES& config, const Ordering& ordering) const;
 
 	private: