diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/02.geometrical-optics-foundings/02.refractive-index/topic.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/02.geometrical-optics-foundings/02.refractive-index/topic.en.md
deleted file mode 100644
index 4609320ae..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/02.geometrical-optics-foundings/02.refractive-index/topic.en.md
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@@ -1,4 +0,0 @@
----
-title: 'The concept of refractive index'
----
-