diff --git a/marllib.ipynb b/marllib.ipynb
index a9f83548..5fc74258 100644
--- a/marllib.ipynb
+++ b/marllib.ipynb
@@ -50,7 +50,7 @@
    },
    "outputs": [],
    "source": [
-    "!/usr/local/bin/pip install protobuf==3.20.0 marllib==1.0.3 ray[rllib] gym==0.20.0"
+    "!/usr/local/bin/pip install protobuf==3.20.0 marllib==1.0.3 ray[rllib]==1.8 gym==0.20.0 numpy==1.22"
    ]
   },
   {