diff --git a/Boolean_set_operations_2/demo/Boolean_set_operations_2/Qt_widget_circle_segment_2.h b/Boolean_set_operations_2/demo/Boolean_set_operations_2/Qt_widget_circle_segment_2.h
index 016ed20cee0..c9bd102b538 100644
--- a/Boolean_set_operations_2/demo/Boolean_set_operations_2/Qt_widget_circle_segment_2.h
+++ b/Boolean_set_operations_2/demo/Boolean_set_operations_2/Qt_widget_circle_segment_2.h
@@ -17,8 +17,8 @@
 //
 // Author(s)     : Baruch Zukerman <baruchzu@post.tau.ac.il>
 
-#ifndef QT_WIDGET_CIRCLE_SEGMENT_2_H
-#define QT_WIDGET_CIRCLE_SEGMENT_2_H
+#ifndef CGAL_QT_WIDGET_CIRCLE_SEGMENT_2_H
+#define CGAL_QT_WIDGET_CIRCLE_SEGMENT_2_H
 
 #include <CGAL/IO/Qt_widget.h>
 #include <CGAL/Arr_traits_2/Circle_segment_2.h>
diff --git a/Boolean_set_operations_2/demo/Boolean_set_operations_2/typedefs.h b/Boolean_set_operations_2/demo/Boolean_set_operations_2/typedefs.h
index d78112ae88e..42660cb4c82 100644
--- a/Boolean_set_operations_2/demo/Boolean_set_operations_2/typedefs.h
+++ b/Boolean_set_operations_2/demo/Boolean_set_operations_2/typedefs.h
@@ -16,8 +16,8 @@
 // 
 //
 // Author(s)     : Baruch Zukerman <baruchzu@post.tau.ac.il>
-#ifndef TYPEDEFS_H
-#define TYPEDEFS_H
+#ifndef CGAL_TYPEDEFS_H
+#define CGAL_TYPEDEFS_H
 
 #include <CGAL/Cartesian.h>
 #include <CGAL/Quotient.h>