diff --git a/CSV_preparation.ipynb b/CSV_preparation.ipynb
index 9edff0c..dac11c6 100644
--- a/CSV_preparation.ipynb
+++ b/CSV_preparation.ipynb
@@ -951,7 +951,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "#### 9.1 Scatter plot"
+    "#### 8.1 Scatter plot"
    ]
   },
   {
@@ -970,7 +970,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "#### 9.2 [Violin plot](https://chartio.com/learn/charts/violin-plot-complete-guide/)"
+    "#### 8.2 [Violin plot](https://chartio.com/learn/charts/violin-plot-complete-guide/)"
    ]
   },
   {
@@ -988,7 +988,7 @@
    "cell_type": "markdown",
    "metadata": {},
    "source": [
-    "#### 9.3 Histogram plot"
+    "#### 8.3 Histogram plot"
    ]
   },
   {
@@ -1065,11 +1065,35 @@
     "<li>Generate two superimposed histograms of the volume distributions in the left hemisphere (left striatum, thalamus and globus pallidus) and right hemisphere (right striatum, thalamus and globus pallidus)</li>\n",
     "</ol>"
    ]
+  },
+  {
+   "cell_type": "markdown",
+   "metadata": {},
+   "source": [
+    "# Supplementary\n",
+    "\n",
+    "### Interactive plots with Plotly Python\n",
+    "\n",
+    "* FYI: Plotly is based in Montreal!\n",
+    "* [Superb documentation](https://plotly.com/python/)\n",
+    "* Plotly express is more \"higher-level\" (tons of parameters are already set for you); can save you time but is less flexible\n",
+    "\n",
+    "### Bringing it to the next level: making an App with Dash\n",
+    "* Documentation [here](https://dash.plotly.com/)\n",
+    "* html + Python"
+   ]
+  },
+  {
+   "cell_type": "code",
+   "execution_count": null,
+   "metadata": {},
+   "outputs": [],
+   "source": []
   }
  ],
  "metadata": {
   "kernelspec": {
-   "display_name": "Python 3",
+   "display_name": "Python 3 (ipykernel)",
    "language": "python",
    "name": "python3"
   },
@@ -1083,7 +1107,7 @@
    "name": "python",
    "nbconvert_exporter": "python",
    "pygments_lexer": "ipython3",
-   "version": "3.8.8"
+   "version": "3.8.13"
   }
  },
  "nbformat": 4,