From 4e08b15403c4ea4be878061c4d1a23e23e8fa4fa Mon Sep 17 00:00:00 2001
From: Claude Meny <claude.meny@irap.omp.eu>
Date: Sun, 30 Aug 2020 10:48:34 +0200
Subject: [PATCH] Update textbook.fr.md

---
 .../04.reference-frames-coordinate-systems/textbook.fr.md    | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md
index 0e045f4db..79b1afc10 100644
--- a/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md
+++ b/00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/04.reference-frames-coordinate-systems/textbook.fr.md
@@ -294,6 +294,11 @@ $`A=\displaystyle\oiint_{S_{\bigcirc}} dA`$<br>
 [FR] Calcul intégral de l'aire $`A`$ d'une surface ouverte $`S_{\smallsmile}`$ macroscopique :<br>
 [EN] Integral calculus of the area $`A`$ of a macroscopic open surface $`A_{\smallsmile}`$ :<br>
 $`A=\displaystyle\iint_{S_{\smallsmile}} dA`$<br>
+[ES] Esta diferencia en la escritura es muy importante. Por ejemplo en electromagnetismo :<br>
+[FR] Cette différence d'écriture est très importante. Par exemple en électromagnétisme :<br>
+[EN] This difference in writing is very important. For example in electromagnetism :<br>
+$`\forall S_{\circ}  \Oiint_{S_{\smallsmile}} \overrightarrow{B}\cdot\overightarrow{dA}=0`$,<br>
+en general $`\iint_{S_{\smallsmile}} \overrightarrow{B}\cdot\overightarrow{dA}\ne 0`$