diff --git a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/02.new-course-overview/cheatsheet.en.md b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/02.new-course-overview/cheatsheet.en.md
index 10d788880..193cd24fe 100644
--- a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/02.new-course-overview/cheatsheet.en.md
+++ b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/03.physical-system-versus-optical-system/02.new-course-overview/cheatsheet.en.md
@@ -1,5 +1,7 @@
 ---
 title: 'new course  : overview'
+published: false
+visible: false
 ---
 
 new course  : overview
\ No newline at end of file