--- /dev/null
+(**************************************************************************)
+(* ___ *)
+(* ||M|| *)
+(* ||A|| A project by Andrea Asperti *)
+(* ||T|| *)
+(* ||I|| Developers: *)
+(* ||T|| The HELM team. *)
+(* ||A|| http://helm.cs.unibo.it *)
+(* \ / *)
+(* \ / This file is distributed under the terms of the *)
+(* v GNU General Public License Version 2 *)
+(* *)
+(**************************************************************************)
+
+include "static_2/syntax/theq_theq.ma".
+include "basic_2/rt_transition/cnh_cnh.ma".
+include "basic_2/rt_computation/cpms.ma".
+
+(* T-BOUND CONTEXT-SENSITIVE PARALLEL RT-COMPUTATION FOR TERMS **************)
+
+(* Inversion lemmas with normal terms for head t-unbound rt-transition ******)
+
+lemma cpms_inv_cnh_sn (h) (n) (G) (L):
+ ∀T1,T2. ⦃G,L⦄ ⊢ T1 ➡*[n,h] T2 → ⦃G,L⦄ ⊢ ⥲[h] 𝐍⦃T1⦄ → T1 ⩳ T2.
+#h #n #G #L #T1 #T2 #H @(cpms_ind_sn … H) -T1 //
+#n1 #n2 #T1 #T0 #HT10 #_ #IH #HT1
+/4 width=9 by cnh_cpm_trans, theq_trans/
+qed-.