diff --git a/01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/05.optical-instruments-use/01.characterization-of-optical-instruments/01.new-course-main/textbook.en.md b/01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/05.optical-instruments-use/01.characterization-of-optical-instruments/01.new-course-main/textbook.en.md
deleted file mode 100644
index 8b09b293d..000000000
--- a/01.curriculum/01.physics-chemistry-biology/02.Niv2/04.optics/05.optical-instruments-use/01.characterization-of-optical-instruments/01.new-course-main/textbook.en.md
+++ /dev/null
@@ -1,5 +0,0 @@
----
-title: 'new course : main'
----
-
-new course : main
\ No newline at end of file