Update textbook.fr.md

00.brainstorming-pedagogical-teams/40.collection-existing-pedagogical-content/50.electromagnetism/40.n4/10.main/textbook.fr.md

@@ -274,11 +274,11 @@ $`\displaystyle\oiint_S\overrightarrow{B}\cdot\overrightarrow{dS}=0`$
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-*[ELECMAG4-10]*
+*[ELECMAG4-20]*
 
 [ES] (auto-trad) *Ley de Gauss = teorema de Gauss* <br>
 [FR] (CME)  *Théorème de Gauss* <br>
-[FR](auto-trad) *Gauss' theorem* <br>
+[EN] (auto-trad) *Gauss' theorem* <br>
 
 $`\displaystyle\iiint_{\tau} div\overrightarrow{E} \cdot d\tau= \displaystyle\iiint_{\tau}
 \dfrac{\rho}{\epsilon_0} \cdot d\tau = \dfrac{1}{\epsilon_0} \cdot \iiint_{\tau} \rho