diff --git a/README.md b/README.md
index 4bea654..cc2d1c2 100644
--- a/README.md
+++ b/README.md
@@ -8,10 +8,9 @@ Notebooks are available as interactive environement through
 [Binder](https://mybinder.org/), static `html` and `pdf`.
 
 - notebook on Perturbation-Optimization algorithm :
-  [![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/orieux/notebooks/master?filepath=The%20Perturbation-Optimisation%20Algorithm.ipynb)
-  /
-  [html](https://github.com/orieux/notebooks/blob/master/The%20Perturbation-Optimisation%20Algorithm.html)
-  / [pdf](https://github.com/orieux/notebooks/blob/master/The%20Perturbation-Optimisation%20Algorithm.pdf)
+  * [![Binder](https://mybinder.org/badge_logo.svg)](https://mybinder.org/v2/gh/orieux/notebooks/master?filepath=The%20Perturbation-Optimisation%20Algorithm.ipynb)
+  * [html](https://github.com/orieux/notebooks/blob/master/The%20Perturbation-Optimisation%20Algorithm.html)
+  * [pdf](https://github.com/orieux/notebooks/blob/master/The%20Perturbation-Optimisation%20Algorithm.pdf)
 
 orieux@l2s.centralesupelec.fr