diff -r 4c7b3eec7375 -r 923a30d143df .hgtags
--- a/.hgtags	Tue Sep 03 15:24:24 2019 +0200
+++ b/.hgtags	Tue Sep 03 15:24:39 2019 +0200
@@ -1,3 +1,4 @@
 d61d51765a02aecd2b1daea286a80ca5458bc948 Isabelle2014/Isac
 2f1b2854927a67d0f66d5ab8f17f40933e30f5a1 Isac2015
 5535bdba43b686dde7a05c25e07fc9d3b55fdf46 isabisac17
+4c7b3eec73750d131ab89aff0ae669cbe7e078bd isabisac18