diff --git a/Concurrent Systems/notes/11 - non so cosa faremo oggi.md b/Concurrent Systems/notes/11 - non so cosa faremo oggi.md
index fdf4663..ccc887f 100644
--- a/Concurrent Systems/notes/11 - non so cosa faremo oggi.md	
+++ b/Concurrent Systems/notes/11 - non so cosa faremo oggi.md	
@@ -14,5 +14,7 @@ Automata Behaviour: language equivalence
 
 ![](../../Pasted%20image%2020250408091924.png)
 By considering the starting states as also final, they both generate the same language, i.e.:
-				(20.(tea + 20.coffee))∗ = (20.tea + 20.20.coffee)∗
+$$(20.(tea + 20.coffee))∗ = (20.tea + 20.20.coffee)∗$$
 
+
+But, do they behave the same from the point of view of an external observer??