diff --git a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/10.mathematical-tools/20.reference-frames-coordinate-systems/textbook.es.md b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/10.mathematical-tools/20.reference-frames-coordinate-systems/textbook.es.md
index a40210fab..16fcf8821 100644
--- a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/10.mathematical-tools/20.reference-frames-coordinate-systems/textbook.es.md
+++ b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/10.mathematical-tools/20.reference-frames-coordinate-systems/textbook.es.md
@@ -516,7 +516,7 @@ $`\varphi\in[0,2\pi[`$ et $`z\in\mathbb{R}=]-\infty ,+\infty\,[`$.
 
 * *CS350*
 
-<details markdown=1>
+!<details markdown=1>
 ! <summary>
 ! Notations sur les ensembles de nombres réels 
 ! </summary>