diff --git a/alto__text.xsl b/alto__text.xsl
index 640bc68..b12264b 100644
--- a/alto__text.xsl
+++ b/alto__text.xsl
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.1" encoding="UTF-8"?>
 <!--
 Author:  konstantin baierer
 License: MIT
diff --git a/hocr__text.xsl b/hocr__text.xsl
index 66a09d1..0b3c420 100644
--- a/hocr__text.xsl
+++ b/hocr__text.xsl
@@ -1,4 +1,4 @@
-<?xml version="1.0" encoding="UTF-8"?>
+<?xml version="1.1" encoding="UTF-8"?>
 <!--
 Author:  konstantin baierer
 License: MIT