diff --git a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/02.paraxial-optics-simple-elements/02.spherical-refracting-surface/06.spherical-refracting-surface-level-down/page.en.md b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/02.paraxial-optics-simple-elements/02.spherical-refracting-surface/06.spherical-refracting-surface-level-down/page.en.md
index 5785895d1..6f0b1cfd3 100644
--- a/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/02.paraxial-optics-simple-elements/02.spherical-refracting-surface/06.spherical-refracting-surface-level-down/page.en.md
+++ b/01.curriculum/01.physics-chemistry-biology/03.Niv3/02.Geometrical-optics/05.paraxial-optics/02.paraxial-optics-simple-elements/02.spherical-refracting-surface/06.spherical-refracting-surface-level-down/page.en.md
@@ -1,5 +1,7 @@
 ---
 title: 'Plane refracting surface (previous level)'
+published: false
+visible: false
 ---
 
 course : level-1