diff --git a/gtsam/nonlinear/nonlinear.i b/gtsam/nonlinear/nonlinear.i
index dceb0c308..9f19141e1 100644
--- a/gtsam/nonlinear/nonlinear.i
+++ b/gtsam/nonlinear/nonlinear.i
@@ -527,7 +527,7 @@ template<class BaseOptimizerParameters>
 class GncParams {
   GncParams(const BaseOptimizerParameters& baseOptimizerParams);
   GncParams();
-  void print(const std::string& str) const;
+  void print(const string& str) const;
 };
   
 #include <gtsam/nonlinear/NonlinearOptimizer.h>