diff --git a/PhysicsTools/Utilities/interface/SimplifyRatio.h b/PhysicsTools/Utilities/interface/SimplifyRatio.h
index a53f93aa337bc..cfe3ff5d7e14e 100644
--- a/PhysicsTools/Utilities/interface/SimplifyRatio.h
+++ b/PhysicsTools/Utilities/interface/SimplifyRatio.h
@@ -7,9 +7,12 @@
 #include "PhysicsTools/Utilities/interface/Minus.h"
 #include "PhysicsTools/Utilities/interface/Fraction.h"
 #include "PhysicsTools/Utilities/interface/DecomposePower.h"
+#include "PhysicsTools/Utilities/interface/ParametricTrait.h"
 
 #include "PhysicsTools/Utilities/interface/Simplify_begin.h"
 
+#include <boost/mpl/if.hpp>
+
 namespace funct {
 
   // 0 / a = 0