diff --git a/Optimal_bounding_box/include/CGAL/Optimal_bounding_box/Oriented_bounding_box_traits.h b/Optimal_bounding_box/include/CGAL/Optimal_bounding_box/Oriented_bounding_box_traits.h
index 6ab7c1862b4..9b616562569 100644
--- a/Optimal_bounding_box/include/CGAL/Optimal_bounding_box/Oriented_bounding_box_traits.h
+++ b/Optimal_bounding_box/include/CGAL/Optimal_bounding_box/Oriented_bounding_box_traits.h
@@ -15,6 +15,8 @@
 
 #include <CGAL/license/Optimal_bounding_box.h>
 
+#include <CGAL/Aff_transformation_3.h>
+
 #ifdef CGAL_EIGEN3_ENABLED
 #include <CGAL/Eigen_matrix.h>
 #include <Eigen/QR>
diff --git a/Optimal_bounding_box/test/Optimal_bounding_box/test_nelder_mead.cpp b/Optimal_bounding_box/test/Optimal_bounding_box/test_nelder_mead.cpp
index ad1751f915c..bb41c4a021a 100644
--- a/Optimal_bounding_box/test/Optimal_bounding_box/test_nelder_mead.cpp
+++ b/Optimal_bounding_box/test/Optimal_bounding_box/test_nelder_mead.cpp
@@ -1,5 +1,6 @@
-#include <CGAL/Optimal_bounding_box/internal/population.h>
-#include <CGAL/Optimal_bounding_box/internal/nelder_mead_functions.h>
+#include <CGAL/Exact_predicates_inexact_constructions_kernel.h>
+
+#include <CGAL/optimal_bounding_box.h>
 
 #include <iostream>