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 f17dfc792..8d40227c9 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
@@ -28,7 +28,7 @@ et la date dans l'espace et le temps de tout point ou évènement $`M`$.<br>
 $`\Longrightarrow`$ coordinate system : 3+1=4 real numbers which specify the position and the date 
 in space and time of any point or event $`M`$.
 
-* **N1** ($`\leftarrow`$ N2 N3 N4)**<br>
+* **N1 ($`\leftarrow`$ N2 N3 N4)**<br>
 **Coordenadas geográficas / Coordonnées géographiques / Geographic coordinates**<br>
 [ES] para construir: planeta Tierra, polo y hemisferio norte, polo y hemisferio sur. <br>
 \- latitud $`\leftrightarrow`$ paralelos; longitude $`\leftrightarrow`$ meridianos;
@@ -57,15 +57,15 @@ true north; $`l=-\,90° \leftrightarrow`$ geographic south pole. <br>
 \- Links with measurement of angles in degrees with a protractor. <br>
 \- $`1° = 60'`$ (minute of arc); $`1'= 60''`$ (arc second). <br>
 \- a position is written in the order latitude, longitude, altitude.<br>
-<br><br>Ejemplos / Exemples / Examples :<br>
-[ES] [EN]<br>
-\- UNAL-Manizales : $5°03'22.08N'' \quad 75°29'28.37''O \quad 2132m`$<br>
-\- Univ de Guadalajara : $20°40'25.76N'' \quad 103°21'30.62''O \quad 1557m`$<br>
-\- INSA-Toulouse : $43°34'11.67N'' \quad 1°28'03.85''E \quad 2132m`$<br>
-[FR]<br>
-\- UNAL-Manizales : $5°03'22.08N'' \quad 75°29'28,37''O \quad 2132m`$<br>
-\- Univ de Guadalajara : $20°40'25.76N'' \quad 103°21'30,62''O \quad 1557m`$<br>
-\- INSA-Toulouse : $43°34'11.67N'' \quad 1°28'03,85''E \quad 2132m`$<br>
+<br>Ejemplos / Exemples / Examples :<br>
+[ES] [EN] :<br>
+\- UNAL-Manizales : $`5°03'22.08N'' \quad 75°29'28.37''O \quad 2132m`$<br>
+\- Univ de Guadalajara : $`20°40'25.76N'' \quad 103°21'30.62''O \quad 1557m`$<br>
+\- INSA-Toulouse : $`43°34'11.67N'' \quad 1°28'03.85''E \quad 2132m`$<br>
+[FR] :<br>
+\- UNAL-Manizales : $`5°03'22.08N'' \quad 75°29'28,37''O \quad 2132m`$<br>
+\- Univ de Guadalajara : $`20°40'25.76N'' \quad 103°21'30,62''O \quad 1557m`$<br>
+\- INSA-Toulouse : $`43°34'11.67N'' \quad 1°28'03,85''E \quad 2132m`$<br>
 
 
 # En mecánica clásica / En mécanique classique / In classical mechanics