-lemma sstas_fwd_correct: ∀h,g,L,T1,U1,l1. ⦃h, L⦄ ⊢ T1 •[g] ⦃l1, U1⦄ →
- ∀T2. ⦃h, L⦄ ⊢ T1 •*[g] T2 →
- ∃∃U2,l2. ⦃h, L⦄ ⊢ T2 •[g] ⦃l2, U2⦄.
+lemma sstas_fwd_correct: ∀h,g,L,T1,U1,l1. ⦃G, L⦄ ⊢ T1 •[h, g] ⦃l1, U1⦄ →
+ ∀T2. ⦃G, L⦄ ⊢ T1 •*[h, g] T2 →
+ ∃∃U2,l2. ⦃G, L⦄ ⊢ T2 •[h, g] ⦃l2, U2⦄.