diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/02.paraxial-optics-simple-elements/01.elements-revolution-symetry/01.elements-revolution-symetry-main/textbook.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/02.paraxial-optics-simple-elements/01.elements-revolution-symetry/01.elements-revolution-symetry-main/textbook.en.md
deleted file mode 100644
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--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/05.paraxial-optics/02.paraxial-optics-simple-elements/01.elements-revolution-symetry/01.elements-revolution-symetry-main/textbook.en.md
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-title: 'new course : main'
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-
-new course : main
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