diff --git a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/07.optical-instruments-design/01.optical-instruments-characterization/01.new-course-main/textbook.en.md b/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/07.optical-instruments-design/01.optical-instruments-characterization/01.new-course-main/textbook.en.md
deleted file mode 100644
index db2c0a73c..000000000
--- a/01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/07.optical-instruments-design/01.optical-instruments-characterization/01.new-course-main/textbook.en.md
+++ /dev/null
@@ -1,7 +0,0 @@
----
-title: 'new course : main'
-published: false
-visible: false
----
-
-new course : main
\ No newline at end of file