diff --git a/gtsam/linear/NoiseModel.h b/gtsam/linear/NoiseModel.h
index 0351cfabd..4b0e4848d 100644
--- a/gtsam/linear/NoiseModel.h
+++ b/gtsam/linear/NoiseModel.h
@@ -19,6 +19,8 @@
 #pragma once
 
 #include <boost/serialization/nvp.hpp>
+#include <boost/serialization/extended_type_info.hpp>
+#include <boost/serialization/singleton.hpp>
 #include <boost/serialization/shared_ptr.hpp>
 #include <boost/serialization/optional.hpp>
 #include <gtsam/base/Matrix.h>