diff --git a/README.md b/README.md
index bfa4626c244b8f5f5e86a1c5c347cbaa592d3d03..5ef370fedd782d7ba72da59ece556090b1996126 100644
--- a/README.md
+++ b/README.md
@@ -116,7 +116,7 @@ Exercices :
 ### Cours 4 
 
 - Visualisation et interactions ([slides](https://docs.google.com/presentation/d/1BOTQs-mzA9mZ323FuXuCgFeJZjNBPDz7jZQtNY9xlyI/edit))
-- Layouts D3 avancés : [grouped chart](https://docs.google.com/presentation/d/1ZbHPdD8ok5fFEaaMG6kHULpg0S8j8jpVkVqvPw8QZDY/edit#slide=id.g765aa770b7_0_108) ([notebook du cours](https://observablehq.com/d/c50fc359e0d9803e)) stacked graphs, pie chart ([slides](https://docs.google.com/presentation/d/1a79MLat-ftU25Uk7uM2JYfDSlKS-9hp94EnmegvcLg0/edit#slide=id.p)) ([observable du cours](https://observablehq.com/d/17206b80c861edd3))
+- Layouts D3 avancés : [grouped chart](https://docs.google.com/presentation/d/1ZbHPdD8ok5fFEaaMG6kHULpg0S8j8jpVkVqvPw8QZDY/edit#slide=id.g765aa770b7_0_108) ([notebook du cours](https://observablehq.com/d/c50fc359e0d9803e), [notebook 23-24](https://observablehq.com/d/652dbabedf245aea)) stacked graphs, pie chart ([slides](https://docs.google.com/presentation/d/1a79MLat-ftU25Uk7uM2JYfDSlKS-9hp94EnmegvcLg0/edit#slide=id.p)) ([observable du cours](https://observablehq.com/d/17206b80c861edd3))
 - Méthode de prototypage de visualisation ([slides](https://docs.google.com/presentation/d/11kEkZK12C893qzyEDvkIjgFKPmRKFf-KDDOKiwGw6ys/edit))
 - Prototypage papier des visualisations du projet (par groupe)