diff --git a/_toc.yml b/_toc.yml
index 85366de..bc112ba 100644
--- a/_toc.yml
+++ b/_toc.yml
@@ -1,6 +1,7 @@
-- file: lectures/00_images_are_arrays
+format: jb-article
+root: lectures/00_images_are_arrays
+sections:
 - file: lectures/1_image_filters
 - file: lectures/3_morphological_operations
 - file: lectures/4_segmentation
 - file: lectures/three_dimensional_image_processing
-