diff --git a/doc/doxygen.cfg b/doc/doxygen.cfg
index cb398db17..19f69008d 100644
--- a/doc/doxygen.cfg
+++ b/doc/doxygen.cfg
@@ -38,7 +38,7 @@ PROJECT_NAME           = "SIRIUS"
 # could be handy for archiving the generated documentation or if some version
 # control system is used.
 
-PROJECT_NUMBER         = "5.9"
+PROJECT_NUMBER         = "6.1.0"
 
 # Using the PROJECT_BRIEF tag one can provide an optional one line description
 # for a project that appears at the top of each page and should give viewer a