diff --git a/README.md b/README.md
index 9a9335c..3a96329 100755
--- a/README.md
+++ b/README.md
@@ -7,3 +7,5 @@ It is used to collect patches and extensions as pull requests.
 The official home page of bibtexbrowser is <http://www.monperrus.net/martin/bibtexbrowser/>.
 
 Bibtexbrowser is free software; you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation; either version 2 of the License, or (at your option) any later version.
+
+Note: Composer compatible version requires PHP 5+.