diff --git a/sna/3_Network_Analysis.ipynb b/sna/3_Network_Analysis.ipynb
index f497631..8fd5c05 100644
--- a/sna/3_Network_Analysis.ipynb
+++ b/sna/3_Network_Analysis.ipynb
@@ -2173,7 +2173,7 @@
     }
    },
    "source": [
-    "The notebook is freely licensed under under the [Creative Commons Attribution Share-Alike license](https://creativecommons.org/licenses/by/2.0/).  \n",
+    "The notebook is freely licensed under the [Creative Commons Attribution Share-Alike license](https://creativecommons.org/licenses/by/2.0/).  \n",
     "\n",
     "© Carlos A. Iglesias, Universidad Politécnica de Madrid."
    ]