diff --git a/_output.yml b/_output.yml
index d2333b3..030fb1a 100644
--- a/_output.yml
+++ b/_output.yml
@@ -1,8 +1,7 @@
 bookdown::gitbook:
   css: assets/style_ITN.css
   includes:
-    header_includes: GA_Script.Rhtml
-    before_body: assets/big-image-itcr.html
+    before_body: [GA_Script.Rhtml, assets/big-image-itcr.html]
     after_body: assets/footer.html
   highlight: tango
   config: