diff --git a/README.md b/README.md
index e9323ad0e89e3473035c6609506cf4e194e4ebaf..1edb75bdfbffd4b024e28ed0f398049b504b4a03 100644
--- a/README.md
+++ b/README.md
@@ -30,6 +30,7 @@ Check the here the [TODO list](TODO).
 # Tutorials
 
 - [Install and test](install_and_test.md)
+- [Google collab: use the octree with multiple particles per leaf](https://colab.research.google.com/drive/1EObmEt7XK56EpwHh7PQ-viR7PHZ5H0pl)
 - [A refined PM DMO run with fixed timesteps](run_pm_dmo_NFW_fixed_timestep.md)
 - **soon:** A cosmological PM DMO run with fixed timesteps