diff --git a/gtsam/linear/GaussianConditionalUnordered-inl.h b/gtsam/linear/GaussianConditionalUnordered-inl.h
index 25ade2327..9050479ad 100644
--- a/gtsam/linear/GaussianConditionalUnordered-inl.h
+++ b/gtsam/linear/GaussianConditionalUnordered-inl.h
@@ -25,9 +25,9 @@
 namespace gtsam {
 
   /* ************************************************************************* */
-  template<typename PARENTS>
+  template<class PARENTS>
   GaussianConditionalUnordered::GaussianConditionalUnordered(Index key, const Vector& d,
-    const Matrix& R, const PARENTS& parents, const SharedDiagonal& sigmas) :
+    const Matrix& R, const PARENTS& parents, const SharedDiagonal& sigmas, const typename PARENTS::value_type*) :
   BaseFactor(boost::join(boost::assign::cref_list_of<1,typename PARENTS::value_type>(std::make_pair(key, R)), parents), d, sigmas),
     BaseConditional(1) {}
 
diff --git a/gtsam/linear/GaussianConditionalUnordered.h b/gtsam/linear/GaussianConditionalUnordered.h
index c19fcc2cd..3bfc2fccd 100644
--- a/gtsam/linear/GaussianConditionalUnordered.h
+++ b/gtsam/linear/GaussianConditionalUnordered.h
@@ -62,10 +62,11 @@ namespace gtsam {
     /** Constructor with number of arbitrary parents.  \f$ |Rx+sum(Ai*xi)-d| \f$
      *  @tparam PARENTS A container whose value type is std::pair<Key, Matrix>, specifying the
      *          collection of parent keys and matrices. */
-    template<typename PARENTS>
+    template<class PARENTS>
     GaussianConditionalUnordered(Key key, const Vector& d,
       const Matrix& R, const PARENTS& parents,
-      const SharedDiagonal& sigmas = SharedDiagonal());
+      const SharedDiagonal& sigmas = SharedDiagonal(),
+      const typename PARENTS::value_type* = 0);
 
     /** Constructor with arbitrary number of frontals and parents.
     *   @tparam TERMS A container whose value type is std::pair<Key, Matrix>, specifying the