Update cheatsheet.fr.md

10.temporary-m3p2/16.waves/20.n2/05.waves-introduction/10.waves-in-physics/cheatsheet.fr.md

@@ -5,7 +5,7 @@ routable: true
 visible: false
 lessons:
     - 
-        slug: waves-conceptual-and-learning-patterns
+        slug: waves-conceptual-and-learning-patterns-fr
         name: PANORAMA-234 : Les ondes, une vision générale
         order: 1
 ---
@@ -34,6 +34,10 @@ lessons:
 
 ### **Les ondes** *en physique*
 
+<br><br>
+[version multilingue : EN , FR , ES](https://m3p2.com/m3p2/polyglot/emporary-m3p2/waves/n2/waves-introduction/waves-in-physics/)
+<br>
+
 <!--
 # <p style="font-size:70%;text-align: center;">Les ondes en physique</p>
 <p style="font-size:75%;text-align: center;">Naissance du concept d'onde</p>