diff --git a/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpq_d_1.h b/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpq_d_1.h
index 400739489b3..a61564ee62c 100644
--- a/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpq_d_1.h
+++ b/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpq_d_1.h
@@ -22,7 +22,6 @@
 #include <CGAL/Gmpq.h>
 #include <CGAL/Gmpfr.h>
 #include <CGAL/Polynomial.h>
-#include "RS/functors_1.h"
 #include "RS/rs2_isolator_1.h"
 #ifdef CGAL_USE_RS3
 #include "RS/rs23_k_isolator_1.h"
diff --git a/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpz_d_1.h b/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpz_d_1.h
index 5e18409917b..d3aa49dd03d 100644
--- a/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpz_d_1.h
+++ b/Algebraic_kernel_d/include/CGAL/Algebraic_kernel_rs_gmpz_d_1.h
@@ -22,7 +22,6 @@
 #include <CGAL/Gmpz.h>
 #include <CGAL/Gmpfr.h>
 #include <CGAL/Polynomial.h>
-#include "RS/functors_1.h"
 #include "RS/rs2_isolator_1.h"
 #ifdef CGAL_USE_RS3
 #include "RS/rs23_k_isolator_1.h"
diff --git a/Algebraic_kernel_d/include/CGAL/RS/ak_1.h b/Algebraic_kernel_d/include/CGAL/RS/ak_1.h
index e75651879ff..09b2d6c68ee 100644
--- a/Algebraic_kernel_d/include/CGAL/RS/ak_1.h
+++ b/Algebraic_kernel_d/include/CGAL/RS/ak_1.h
@@ -24,6 +24,7 @@
 #include "algebraic_1.h"
 #include "comparator_1.h"
 #include "signat_1.h"
+#include "functors_1.h"
 
 namespace CGAL{
 namespace RS_AK1{