diff --git a/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.en.md b/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.en.md
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--- a/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.en.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-title: 'new course : main'
----
-
-new course : main
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.es.md b/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.es.md
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--- a/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.es.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-title: 'nuevo curso: principal'
----
-
-nuevo curso: principal
\ No newline at end of file
diff --git a/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.fr.md b/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.fr.md
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--- a/01.curriculum/01.physics-chemistry-biology/01.niv1/06.nature-of-light/01.light-intensity/01.light-intensity-main/textbook.fr.md
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@@ -1,5 +0,0 @@
----
-title: 'De l''obscurité à la clareté'
----
-
-nouveau cours : principal
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