diff --git a/Extended_Finite_State_Machines/ROOT b/Extended_Finite_State_Machines/ROOT
index 79f5709..3cc25e6 100644
--- a/Extended_Finite_State_Machines/ROOT
+++ b/Extended_Finite_State_Machines/ROOT
@@ -1,6 +1,6 @@
 chapter AFP
 
-session Extended_Finite_State_Machines (AFP) = "HOL-Library" +
+session "Extended_Finite_State_Machines-devel" (AFP) = "HOL-Library" +
 options [timeout = 600] 
 sessions
   FinFun
diff --git a/README.md b/README.md
index 2623d91..089223a 100644
--- a/README.md
+++ b/README.md
@@ -11,7 +11,7 @@ submitted, as an update to the existing entry, at a later point in time.
 ## How to build
 
 ```console
-achim@logicalhacking:~$ isabelle build -D Extended_Finite_State_Machines
+achim@logicalhacking:~$ isabelle build -D Extended_Finite_State_Machines-devel
 ```
 
 ## Authors