(* NOTATION FOR THE FORMAL SYSTEM λδ ****************************************)
-notation "hvbox( â\87© [ term 46 s , break term 46 d , break term 46 e ] break term 46 L1 ≡ break term 46 L2 )"
+notation "hvbox( â¬\87 [ term 46 s , break term 46 d , break term 46 e ] break term 46 L1 ≡ break term 46 L2 )"
non associative with precedence 45
for @{ 'RDrop $s $d $e $L1 $L2 }.