diff --git a/.github/workflows/book.yml b/.github/workflows/book.yml
index 1211525..d4aad53 100644
--- a/.github/workflows/book.yml
+++ b/.github/workflows/book.yml
@@ -1,6 +1,6 @@
 name: Book
 
-on: [push]
+on: [push, pull_request]
 
 jobs:
   book: