diff --git a/_bookdown.yml b/_bookdown.yml
index 681d9df..6292462 100644
--- a/_bookdown.yml
+++ b/_bookdown.yml
@@ -17,8 +17,8 @@ rmd_files: [
   "program.Rmd",
   "pipes.Rmd",
   "functions.Rmd",
-  "iteration.Rmd",
   "data-structures.Rmd",
+  "iteration.Rmd",
   "hierarchy.Rmd",
   "science.Rmd",
   "model-vis.Rmd",