diff --git a/Concurrent Systems/notes/9 - Consensus.md b/Concurrent Systems/notes/9 - Consensus.md
index 93db730..7552d8e 100644
--- a/Concurrent Systems/notes/9 - Consensus.md	
+++ b/Concurrent Systems/notes/9 - Consensus.md	
@@ -145,7 +145,7 @@ Every $p_{j}$ that participates in the k-th consensus increases `last_sn_j[i]` b
 - if `π2(LAST_OP[i])` is not changed, then the guard of the IF is false and ⟨“op(par)”,i⟩ is not appended in `invoc_j`
 - otherwise, we have a new invocation from $p_{i}$ (but this can only happen after that ⟨“op(par)”,sn⟩ has been executed)
 
-**Lemma 3:** the local copies $s_{i}$ if all correct processes behave the same and comply with the sequential specification of Z
+**Lemma 3:** the local copies $s_{i}$ of all correct processes behave the same and comply with the sequential specification of Z.
 
 *Proof:*
 - the processes use CONS in the same order `(CONS[1], CONS[2], …)`