diff --git a/apps/sample/CMakeLists.txt b/apps/sample/CMakeLists.txt
index 939b7992d..fab58ebea 100644
--- a/apps/sample/CMakeLists.txt
+++ b/apps/sample/CMakeLists.txt
@@ -15,7 +15,7 @@ set(VCG_EXAMPLE_PROJECTS
 	trimesh_align_pair
 	trimesh_allocate
 	trimesh_attribute
-	trimesh_attribute_saving
+	trimesh_attribute_ply
 	trimesh_ball_pivoting
 	trimesh_base
 	trimesh_closest
diff --git a/apps/sample/trimesh_attribute_saving/CMakeLists.txt b/apps/sample/trimesh_attribute_ply/CMakeLists.txt
similarity index 58%
rename from apps/sample/trimesh_attribute_saving/CMakeLists.txt
rename to apps/sample/trimesh_attribute_ply/CMakeLists.txt
index 56572ba8f..180267616 100644
--- a/apps/sample/trimesh_attribute_saving/CMakeLists.txt
+++ b/apps/sample/trimesh_attribute_ply/CMakeLists.txt
@@ -1,17 +1,17 @@
 cmake_minimum_required(VERSION 3.13)
-project(trimesh_attribute_saving)
+project(trimesh_attribute_ply)
 
 if (VCG_HEADER_ONLY)
 	set(SOURCES
-		trimesh_attribute_saving.cpp
+		trimesh_attribute_ply.cpp
 		${VCG_INCLUDE_DIRS}/wrap/ply/plylib.cpp)
 endif()
 
-add_executable(trimesh_attribute_saving
+add_executable(trimesh_attribute_ply
 	${SOURCES})
 
 target_link_libraries(
-	trimesh_attribute_saving
+	trimesh_attribute_ply
 	PUBLIC
 		vcglib
 	)
diff --git a/apps/sample/trimesh_attribute_saving/trimesh_attribute_saving.cpp b/apps/sample/trimesh_attribute_ply/trimesh_attribute_ply.cpp
similarity index 97%
rename from apps/sample/trimesh_attribute_saving/trimesh_attribute_saving.cpp
rename to apps/sample/trimesh_attribute_ply/trimesh_attribute_ply.cpp
index f0a46cb5e..8b65e1aca 100644
--- a/apps/sample/trimesh_attribute_saving/trimesh_attribute_saving.cpp
+++ b/apps/sample/trimesh_attribute_ply/trimesh_attribute_ply.cpp
@@ -23,7 +23,7 @@
 /*! \file trimesh_attribute.cpp
 \ingroup code_sample
 
-\brief the minimal example of using the attributes
+\brief the minimal example of saving and loading attributes into PLY
 
 Attributes are a simple mechanism to associate user-defined 'attributes' to the simplicies and to the mesh.
 See the page '\ref attributes' for more details.
@@ -104,6 +104,7 @@ int main()
   vcg::tri::io::PlyInfo piOpen;
   piOpen.AddPerFaceFloatAttribute("MyFaceArea", "FaceArea");
   piOpen.AddPerVertexFloatAttribute("GaussianCurvature");
+  piOpen.AddPerVertexPoint3fAttribute(mi,"InvertedNormal");
   
   
   int ret = vcg::tri::io::ImporterPLY<MyMesh>::Open(mi,"MeshWithCurvature.ply",piOpen);
diff --git a/apps/sample/trimesh_attribute_saving/trimesh_attribute_saving.pro b/apps/sample/trimesh_attribute_ply/trimesh_attribute_ply.pro
similarity index 100%
rename from apps/sample/trimesh_attribute_saving/trimesh_attribute_saving.pro
rename to apps/sample/trimesh_attribute_ply/trimesh_attribute_ply.pro