Deleted 01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/03.reflexion-refraction-raytracing/02.optical-fiber/textbook.en.md, 01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/03.reflexion-refraction-raytracing/02.optical-fiber/textbook.fr.md, 01.curriculum/01.physics-chemistry-biology/03.niv3/02.geometrical-optics/03.reflexion-refraction-raytracing/02.optical-fiber/topic.es.md files