diff --git a/data-visualise.ipynb b/data-visualise.ipynb
index 0335c48..ea3a182 100644
--- a/data-visualise.ipynb
+++ b/data-visualise.ipynb
@@ -703,10 +703,10 @@
     "\n",
     "    ```Python\n",
     "\n",
-    "    (ggplot(penguins, aes(x = species)) +\n",
+    "    (ggplot(penguins, aes(x = "species")) +\n",
     "      geom_bar(color = \"red\"))\n",
     "\n",
-    "    (ggplot(penguins, aes(x = species)) +\n",
+    "    (ggplot(penguins, aes(x = "species")) +\n",
     "      geom_bar(fill = \"red\"))\n",
     "    ```\n",
     "\n",