diff --git a/apps/sample/trimesh_curvature/CMakeLists.txt b/apps/sample/trimesh_curvature/CMakeLists.txt
index a09fe6e1..57265ce7 100644
--- a/apps/sample/trimesh_curvature/CMakeLists.txt
+++ b/apps/sample/trimesh_curvature/CMakeLists.txt
@@ -3,7 +3,8 @@ project(trimesh_curvature)
 
 if (VCG_HEADER_ONLY)
 	set(SOURCES
-		trimesh_curvature.cpp)
+		trimesh_curvature.cpp
+		${VCG_INCLUDE_DIRS}/wrap/ply/plylib.cpp)
 endif()
 
 add_executable(trimesh_curvature