diff --git a/book/_toc.yml b/book/_toc.yml
index 86e598f..9174d91 100644
--- a/book/_toc.yml
+++ b/book/_toc.yml
@@ -70,6 +70,7 @@ parts:
     # - file: pages/subcircuits
     # - file: pages/design_for_testing
     - file: pages/mzi
+    - file: pages/mzi_layout
   - caption: Active Device Design and Simulation
     chapters:
     - file: pages/advanced_components