diff --git a/.obsidian/workspace.json b/.obsidian/workspace.json
index 72c8d75..9234e2a 100644
--- a/.obsidian/workspace.json
+++ b/.obsidian/workspace.json
@@ -33,8 +33,7 @@
               "title": "class 9"
             }
           }
-        ],
-        "currentTab": 1
+        ]
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     ],
     "direction": "vertical"
@@ -203,10 +202,10 @@
       "companion:Toggle completion": false
     }
   },
-  "active": "f158d16483dc1627",
+  "active": "aa7ed62f1bcd712a",
   "lastOpenFiles": [
-    "Concurrent Systems/notes/9 - Consensus.md",
     "Concurrent Systems/slides/class 9.pdf",
+    "Concurrent Systems/notes/9 - Consensus.md",
     "Concurrent Systems/notes/2 - Fast mutex by Lamport.md",
     "Concurrent Systems/notes/3a - Hardware primitives & Lamport Bakery algorithm.md",
     "Concurrent Systems/notes/7- MUTEX-free concurrency.md",
diff --git a/Concurrent Systems/notes/9 - Consensus.md b/Concurrent Systems/notes/9 - Consensus.md
index d9e8ce1..93db730 100644
--- a/Concurrent Systems/notes/9 - Consensus.md	
+++ b/Concurrent Systems/notes/9 - Consensus.md	
@@ -135,7 +135,7 @@ It suffices to prove that ∃ k s.t. `CONS[k].propose(-)` returns a list that co
 
 As shown before, every invocation is executed; we have to show that this cannot happen more than once.
 
-**Lemma 2:** metti nome lemma
+**Lemma 2:** all operations invoked by processes are executed exactly once
 If $p_i$ has inserted ⟨“op(par)”,sn⟩ in `LAST_OP[i]`, it cannot invoke another operation until ⟨“op(par)”,sn⟩ appears in a list chosen by the consensus
 - the sequence number of `LAST_OP[i]` can increase only after ⟨“op(par)”,sn⟩ has been executed