diff --git a/module3/exo3/exercice_en.ipynb b/module3/exo3/exercice_en.ipynb
index e1d27abc4bf56bb94e932bdb961100e0619def69..fe56feab9bd28e0cf21abc14bd4f8f63e2487bde 100644
--- a/module3/exo3/exercice_en.ipynb
+++ b/module3/exo3/exercice_en.ipynb
@@ -3,7 +3,13 @@
   {
    "cell_type": "markdown",
    "metadata": {},
-   "source": []
+   "source": [
+    "### Research reproductable: work in pairs\n",
+    "\n",
+    "#### Subject 2: Purchasing power of English workers from the 16th to the 19th century\n",
+    "\n",
+    "William Playfair "
+   ]
   },
   {
    "cell_type": "code",