diff --git a/book.md b/book.md
index f8ae954..8536b70 100644
--- a/book.md
+++ b/book.md
@@ -2,6 +2,7 @@
 title: "Cripto libretto"
 author: Unit hacklab - unit@paranoici.org
 date: 12 dicembre 2019
+lang: it-IT
 ---
 
 \newpage