(* GENERAL NOTATION USED BY THE FORMAL SYSTEM λδ ****************************)
-notation "hvbox( L1 â\8b\93 break term 46 L2 â\89¡ break term 46 L )"
+notation "hvbox( L1 â\8b\93 break term 46 L2 â\89\98 break term 46 L )"
non associative with precedence 45
for @{ 'RUnion $L1 $L2 $L }.