diff --git a/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/CMakeLists.txt b/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/CMakeLists.txt
index 0f54382257e..c389e9a0d3d 100644
--- a/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/CMakeLists.txt
+++ b/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/CMakeLists.txt
@@ -25,6 +25,7 @@ if(CGAL_FOUND AND CGAL_Qt5_FOUND AND Qt5_FOUND AND (CGAL_Core_FOUND OR LEDA_FOUN
 
   # cpp files
   add_executable ( HDT2 HDT2.cpp ${CGAL_Qt5_RESOURCE_FILES} ${RESOURCE_FILES} ${UIS})
+  target_include_directories(HDT2 PRIVATE ./ ./include)
   add_to_cached_list( CGAL_EXECUTABLE_TARGETS HDT2 )
   target_link_libraries ( HDT2 CGAL::CGAL CGAL::CGAL_Qt5 CGAL::CGAL_Core Qt5::Widgets)
 else()
diff --git a/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/HDT2.cpp b/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/HDT2.cpp
index 9fbb9e6d730..1d32eba2c8f 100644
--- a/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/HDT2.cpp
+++ b/Hyperbolic_triangulation_2/demo/Hyperbolic_triangulation_2/HDT2.cpp
@@ -11,7 +11,7 @@
 #else
   #include <CGAL/Cartesian.h>
   #include <CGAL/Hyperbolic_Delaunay_triangulation_traits_2.h>
-  #include <internal/Qt/HyperbolicPainterOstream.h>
+  #include "internal/Qt/HyperbolicPainterOstream.h"
 #endif
 
 #include <CGAL/Hyperbolic_Delaunay_triangulation_2.h>