+(* Basic_1: was: nf2_pr3_unfold *)
+lemma cprs_inv_cnf1: ∀L,T,U. L ⊢ T ➡* U → L ⊢ 𝐍⦃T⦄ → T = U.
+#L #T #U #H @(cprs_ind_dx … H) -T //
+#T0 #T #H1T0 #_ #IHT #H2T0
+lapply (H2T0 … H1T0) -H1T0 #H destruct /2 width=1/
+qed-.
+
+lemma tprs_inv_cnf1: ∀T,U. T ➡* U → ⋆ ⊢ 𝐍⦃T⦄ → T = U.
+/3 width=3 by tprs_cprs, cprs_inv_cnf1/ qed-.
+
+(* Basic_1: removed theorems 10:
+ clear_pr3_trans pr3_cflat pr3_gen_bind
+ pr3_head_1 pr3_head_2 pr3_head_21 pr3_head_12
+ pr3_iso_appl_bind pr3_iso_appls_appl_bind pr3_iso_appls_bind
+*)