diff --git a/book/_config.yml b/book/_config.yml
index b32aa88..0f4b175 100644
--- a/book/_config.yml
+++ b/book/_config.yml
@@ -42,9 +42,9 @@ sphinx:
     html_static_path: ["images"]
     bibtex_default_style: myapastyle
     bibtex_reference_style: author_year_round
-    local_extensions:
-      apastyle: _ext/
-      bracket_citation_style: _ext/
+  local_extensions:
+    apastyle: _ext/
+    bracket_citation_style: _ext/
 
 bibtex_bibfiles: 
   - references.bib