diff --git a/book b/book
index 9bc2bf7..9208888 160000
--- a/book
+++ b/book
@@ -1 +1 @@
-Subproject commit 9bc2bf7138ed9e0e122eebb7b11da6668c98f1d0
+Subproject commit 9208888776227ace87cbde49e225fc711840e047