End NORM_SOUND.
Module Norm_Sound (VSM: VERISTAR_MODEL) : NORM_SOUND with Module VSM := VSM.
Module VSM := VSM.

(* Specifications: *)
Lemma subst_expr_sound v e e' s :
(Var v === e) s -> (expr_denote e' s = expr_denote (subst_expr v e e') s).