prepare release V3.1.1
diff --git a/documentation/conf.py b/documentation/conf.py
index 66b44da..4cff961 100644
--- a/documentation/conf.py
+++ b/documentation/conf.py
@@ -47,7 +47,7 @@
 # The short X.Y version.
 version = '3.1'
 # The full version, including alpha/beta/rc tags.
-release = '3.1.0'
+release = '3.1.1'
 
 # The language for content autogenerated by Sphinx. Refer to documentation
 # for a list of supported languages.