diff --git a/eo/src/eoParetoConstraintFitness.h b/eo/src/eoParetoConstraintFitness.h
index 9e2b2942..c33417ad 100644
--- a/eo/src/eoParetoConstraintFitness.h
+++ b/eo/src/eoParetoConstraintFitness.h
@@ -31,7 +31,7 @@
 #include <stdexcept>
 #include <iostream>
 
-
+#include <eoParetoFitness.h>
 
 /**
   eoParetoOneConstraintFitness class: