diff --git a/.github/requirements-Book.txt b/.github/requirements-Book.txt
index 49f26a3..492645b 100644
--- a/.github/requirements-Book.txt
+++ b/.github/requirements-Book.txt
@@ -1,2 +1,3 @@
 jupyter-book
-ghp-import
\ No newline at end of file
+ghp-import
+sphinx-toolbox
\ No newline at end of file
diff --git a/files/_config.yml b/files/_config.yml
index 1e46ce6..ed22c7a 100644
--- a/files/_config.yml
+++ b/files/_config.yml
@@ -33,9 +33,8 @@ sphinx:
       logo:
         image_light: images/logo.png
         image_dark: images/logo_negatif.png
-    extensions : [
-    'sphinx_toolbox.tweaks.latex_layout',
-    ]
+    extra_extensions:
+     - "sphinx_toolbox.tweaks.latex_layout"
     html_favicon: images/erc.ico
     html_show_copyright: false
     html_static_path: ['docs']