diff --git a/ml4/2_5_1_Exercise.ipynb b/ml4/2_5_1_Exercise.ipynb
index 70ed781..ad820a3 100644
--- a/ml4/2_5_1_Exercise.ipynb
+++ b/ml4/2_5_1_Exercise.ipynb
@@ -200,13 +200,15 @@
    "source": [
     "## Optional. Optimizing ML hyperparameters\n",
     "\n",
-    "One of the applications of Genetic Algorithms is the optimization of ML hyperparameters. Previously we have used GridSearch from Scikit. Using (sklearn-deap)[[References](#References)], optimize the Titatic hyperparameters using both GridSearch and Genetic Algorithms. \n",
+    "One of the applications of Genetic Algorithms is the optimization of ML hyperparameters. Previously, we have used GridSearch from Scikit. Using (sklearn-deap)[[References](#References)], optimize the Titatic hyperparameters using both GridSearch and Genetic Algorithms. \n",
     "\n",
     "The same exercise (using the digits dataset) can be found in this [notebook](https://github.com/rsteca/sklearn-deap/blob/master/test.ipynb).\n",
     "\n",
     "Submit a notebook where you include well-crafted conclusions about the exercises, discussing the pros and cons of using genetic algorithms for this purpose.\n",
     "\n",
-    "Note: There is a problem with Scikit version 0.24. Comment on the different approaches."
+    "Note: There is a problem with Scikit version 0.24. Comment on the different approaches.",
+    "\n",
+    "You can also use the library (sklearn-genetic-opt)[https://sklearn-genetic-opt.readthedocs.io/en/stable/index.html]"
    ]
   },
   {
@@ -256,7 +258,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "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."
    ]