diff --git a/external/book b/external/book
index 0aa844b15af5f09d1f7c9effa60ea0da1cd0c84f..bc32e86418714ff52fa8b698862751b199e167c0 160000
--- a/external/book
+++ b/external/book
@@ -1 +1 @@
-Subproject commit 0aa844b15af5f09d1f7c9effa60ea0da1cd0c84f
+Subproject commit bc32e86418714ff52fa8b698862751b199e167c0