diff --git a/resources/lang/et/entities.php b/resources/lang/et/entities.php
index 24c9e6148..4e1f28fdc 100644
--- a/resources/lang/et/entities.php
+++ b/resources/lang/et/entities.php
@@ -171,6 +171,7 @@ return [
     'chapters_permissions_active' => 'Peatüki õigused on aktiivsed',
     'chapters_permissions_success' => 'Peatüki õigused muudetud',
     'chapters_search_this' => 'Otsi sellest peatükist',
+    'chapter_sort_book' => 'Sort Book',
 
     // Pages
     'page' => 'Leht',