diff -r 44588e355ca8 -r 373d95cf1b98 src/HOL/ROOT
--- a/src/HOL/ROOT	Fri Sep 06 15:45:05 2019 +0200
+++ b/src/HOL/ROOT	Fri Sep 06 15:50:57 2019 +0200
@@ -326,6 +326,8 @@
 
     The Isabelle Algebraic Library.
   "
+  sessions
+    "HOL-Cardinals"
   theories
     (* Orders and Lattices *)
     Galois_Connection    (* Knaster-Tarski theorem and Galois connections *)